Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1469 insertions, 0 deletions

diff --git a/dom/html/nsGenericHTMLElement.h b/dom/html/nsGenericHTMLElement.h
new file mode 100644
index 0000000000..4dae91a5ef
--- /dev/null
+++ b/dom/html/nsGenericHTMLElement.h
@@ -0,0 +1,1469 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef nsGenericHTMLElement_h___
+#define nsGenericHTMLElement_h___
+
+#include "mozilla/Attributes.h"
+#include "mozilla/EventForwards.h"
+#include "nsMappedAttributeElement.h"
+#include "nsNameSpaceManager.h"  // for kNameSpaceID_None
+#include "nsIFormControl.h"
+#include "nsGkAtoms.h"
+#include "nsContentCreatorFunctions.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/DOMRect.h"
+#include "mozilla/dom/ValidityState.h"
+#include "mozilla/dom/PopoverData.h"
+#include "mozilla/dom/ToggleEvent.h"
+
+class nsDOMTokenList;
+class nsIFormControlFrame;
+class nsIFrame;
+class nsILayoutHistoryState;
+class nsIURI;
+struct nsSize;
+
+namespace mozilla {
+class EditorBase;
+class ErrorResult;
+class EventChainPostVisitor;
+class EventChainPreVisitor;
+class EventChainVisitor;
+class EventListenerManager;
+class PresState;
+namespace dom {
+class ElementInternals;
+class HTMLFormElement;
+}  // namespace dom
+}  // namespace mozilla
+
+using nsGenericHTMLElementBase = nsMappedAttributeElement;
+
+/**
+ * A common superclass for HTML elements
+ */
+class nsGenericHTMLElement : public nsGenericHTMLElementBase {
+ public:
+  using Element::Focus;
+  using Element::SetTabIndex;
+  explicit nsGenericHTMLElement(
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
+      : nsGenericHTMLElementBase(std::move(aNodeInfo)) {
+    NS_ASSERTION(mNodeInfo->NamespaceID() == kNameSpaceID_XHTML,
+                 "Unexpected namespace");
+    AddStatesSilently(mozilla::dom::ElementState::LTR);
+    SetFlags(NODE_HAS_DIRECTION_LTR);
+  }
+
+  NS_INLINE_DECL_REFCOUNTING_INHERITED(nsGenericHTMLElement,
+                                       nsGenericHTMLElementBase)
+
+  NS_IMPL_FROMNODE(nsGenericHTMLElement, kNameSpaceID_XHTML)
+
+  // From Element
+  nsresult CopyInnerTo(mozilla::dom::Element* aDest);
+
+  void GetTitle(mozilla::dom::DOMString& aTitle) {
+    GetHTMLAttr(nsGkAtoms::title, aTitle);
+  }
+  void SetTitle(const nsAString& aTitle) {
+    SetHTMLAttr(nsGkAtoms::title, aTitle);
+  }
+  void GetLang(mozilla::dom::DOMString& aLang) {
+    GetHTMLAttr(nsGkAtoms::lang, aLang);
+  }
+  void SetLang(const nsAString& aLang) { SetHTMLAttr(nsGkAtoms::lang, aLang); }
+  bool Translate() const override;
+  void SetTranslate(bool aTranslate, mozilla::ErrorResult& aError) {
+    SetHTMLAttr(nsGkAtoms::translate, aTranslate ? u"yes"_ns : u"no"_ns,
+                aError);
+  }
+  void GetDir(nsAString& aDir) { GetHTMLEnumAttr(nsGkAtoms::dir, aDir); }
+  void SetDir(const nsAString& aDir, mozilla::ErrorResult& aError) {
+    SetHTMLAttr(nsGkAtoms::dir, aDir, aError);
+  }
+  void GetPopover(nsString& aPopover) const;
+  void SetPopover(const nsAString& aPopover, mozilla::ErrorResult& aError) {
+    SetOrRemoveNullableStringAttr(nsGkAtoms::popover, aPopover, aError);
+  }
+  bool Hidden() const { return GetBoolAttr(nsGkAtoms::hidden); }
+  void SetHidden(bool aHidden, mozilla::ErrorResult& aError) {
+    SetHTMLBoolAttr(nsGkAtoms::hidden, aHidden, aError);
+  }
+  bool Inert() const { return GetBoolAttr(nsGkAtoms::inert); }
+  void SetInert(bool aInert, mozilla::ErrorResult& aError) {
+    SetHTMLBoolAttr(nsGkAtoms::inert, aInert, aError);
+  }
+  MOZ_CAN_RUN_SCRIPT void Click(mozilla::dom::CallerType aCallerType);
+  void GetAccessKey(nsString& aAccessKey) {
+    GetHTMLAttr(nsGkAtoms::accesskey, aAccessKey);
+  }
+  void SetAccessKey(const nsAString& aAccessKey, mozilla::ErrorResult& aError) {
+    SetHTMLAttr(nsGkAtoms::accesskey, aAccessKey, aError);
+  }
+  void GetAccessKeyLabel(nsString& aAccessKeyLabel);
+  virtual bool Draggable() const {
+    return AttrValueIs(kNameSpaceID_None, nsGkAtoms::draggable,
+                       nsGkAtoms::_true, eIgnoreCase);
+  }
+  void SetDraggable(bool aDraggable, mozilla::ErrorResult& aError) {
+    SetHTMLAttr(nsGkAtoms::draggable, aDraggable ? u"true"_ns : u"false"_ns,
+                aError);
+  }
+  void GetContentEditable(nsString& aContentEditable) {
+    ContentEditableTristate value = GetContentEditableValue();
+    if (value == eTrue) {
+      aContentEditable.AssignLiteral("true");
+    } else if (value == eFalse) {
+      aContentEditable.AssignLiteral("false");
+    } else {
+      aContentEditable.AssignLiteral("inherit");
+    }
+  }
+  void SetContentEditable(const nsAString& aContentEditable,
+                          mozilla::ErrorResult& aError) {
+    if (aContentEditable.LowerCaseEqualsLiteral("inherit")) {
+      UnsetHTMLAttr(nsGkAtoms::contenteditable, aError);
+    } else if (aContentEditable.LowerCaseEqualsLiteral("true")) {
+      SetHTMLAttr(nsGkAtoms::contenteditable, u"true"_ns, aError);
+    } else if (aContentEditable.LowerCaseEqualsLiteral("false")) {
+      SetHTMLAttr(nsGkAtoms::contenteditable, u"false"_ns, aError);
+    } else {
+      aError.Throw(NS_ERROR_DOM_SYNTAX_ERR);
+    }
+  }
+  bool IsContentEditable() {
+    for (nsIContent* node = this; node; node = node->GetParent()) {
+      nsGenericHTMLElement* element = FromNode(node);
+      if (element) {
+        ContentEditableTristate value = element->GetContentEditableValue();
+        if (value != eInherit) {
+          return value == eTrue;
+        }
+      }
+    }
+    return false;
+  }
+
+  mozilla::dom::PopoverAttributeState GetPopoverAttributeState() const;
+  void PopoverPseudoStateUpdate(bool aOpen, bool aNotify);
+  bool PopoverOpen() const;
+  bool CheckPopoverValidity(mozilla::dom::PopoverVisibilityState aExpectedState,
+                            Document* aExpectedDocument, ErrorResult& aRv);
+  /** Returns true if the event has been cancelled. */
+  MOZ_CAN_RUN_SCRIPT bool FireToggleEvent(
+      mozilla::dom::PopoverVisibilityState aOldState,
+      mozilla::dom::PopoverVisibilityState aNewState, const nsAString& aType);
+  MOZ_CAN_RUN_SCRIPT void QueuePopoverEventTask(
+      mozilla::dom::PopoverVisibilityState aOldState);
+  MOZ_CAN_RUN_SCRIPT void RunPopoverToggleEventTask(
+      mozilla::dom::PopoverToggleEventTask* aTask,
+      mozilla::dom::PopoverVisibilityState aOldState);
+  MOZ_CAN_RUN_SCRIPT void ShowPopover(ErrorResult& aRv);
+  MOZ_CAN_RUN_SCRIPT_BOUNDARY void HidePopoverWithoutRunningScript();
+  MOZ_CAN_RUN_SCRIPT void HidePopoverInternal(bool aFocusPreviousElement,
+                                              bool aFireEvents,
+                                              ErrorResult& aRv);
+  MOZ_CAN_RUN_SCRIPT void HidePopover(ErrorResult& aRv);
+  MOZ_CAN_RUN_SCRIPT void TogglePopover(
+      const mozilla::dom::Optional<bool>& aForce, ErrorResult& aRv);
+  MOZ_CAN_RUN_SCRIPT void FocusPopover();
+  void ForgetPreviouslyFocusedElementAfterHidingPopover();
+  MOZ_CAN_RUN_SCRIPT void FocusPreviousElementAfterHidingPopover();
+
+  MOZ_CAN_RUN_SCRIPT void FocusCandidate(Element&, bool aClearUpFocus);
+
+  void SetNonce(const nsAString& aNonce) {
+    SetProperty(nsGkAtoms::nonce, new nsString(aNonce),
+                nsINode::DeleteProperty<nsString>, /* aTransfer = */ true);
+  }
+  void RemoveNonce() { RemoveProperty(nsGkAtoms::nonce); }
+  void GetNonce(nsAString& aNonce) const {
+    nsString* cspNonce = static_cast<nsString*>(GetProperty(nsGkAtoms::nonce));
+    if (cspNonce) {
+      aNonce = *cspNonce;
+    }
+  }
+
+  /** Returns whether a form control should be default-focusable. */
+  bool IsFormControlDefaultFocusable(bool aWithMouse) const;
+
+  /**
+   * Returns the count of descendants (inclusive of this node) in
+   * the uncomposed document that are explicitly set as editable.
+   */
+  uint32_t EditableInclusiveDescendantCount();
+
+  bool Spellcheck();
+  void SetSpellcheck(bool aSpellcheck, mozilla::ErrorResult& aError) {
+    SetHTMLAttr(nsGkAtoms::spellcheck, aSpellcheck ? u"true"_ns : u"false"_ns,
+                aError);
+  }
+
+  MOZ_CAN_RUN_SCRIPT
+  void GetInnerText(mozilla::dom::DOMString& aValue, ErrorResult& aError);
+  MOZ_CAN_RUN_SCRIPT
+  void GetOuterText(mozilla::dom::DOMString& aValue, ErrorResult& aError) {
+    return GetInnerText(aValue, aError);
+  }
+  MOZ_CAN_RUN_SCRIPT void SetInnerText(const nsAString& aValue);
+  MOZ_CAN_RUN_SCRIPT void SetOuterText(const nsAString& aValue,
+                                       ErrorResult& aRv);
+
+  void GetInputMode(nsAString& aValue) {
+    GetEnumAttr(nsGkAtoms::inputmode, nullptr, aValue);
+  }
+  void SetInputMode(const nsAString& aValue, ErrorResult& aRv) {
+    SetHTMLAttr(nsGkAtoms::inputmode, aValue, aRv);
+  }
+  virtual void GetAutocapitalize(nsAString& aValue) const;
+  void SetAutocapitalize(const nsAString& aValue, ErrorResult& aRv) {
+    SetHTMLAttr(nsGkAtoms::autocapitalize, aValue, aRv);
+  }
+
+  void GetEnterKeyHint(nsAString& aValue) const {
+    GetEnumAttr(nsGkAtoms::enterkeyhint, nullptr, aValue);
+  }
+  void SetEnterKeyHint(const nsAString& aValue, ErrorResult& aRv) {
+    SetHTMLAttr(nsGkAtoms::enterkeyhint, aValue, aRv);
+  }
+
+  /**
+   * Determine whether an attribute is an event (onclick, etc.)
+   * @param aName the attribute
+   * @return whether the name is an event handler name
+   */
+  bool IsEventAttributeNameInternal(nsAtom* aName) override;
+
+#define EVENT(name_, id_, type_, struct_) /* nothing; handled by nsINode */
+// The using nsINode::Get/SetOn* are to avoid warnings about shadowing the XPCOM
+// getter and setter on nsINode.
+#define FORWARDED_EVENT(name_, id_, type_, struct_)  \
+  using nsINode::GetOn##name_;                       \
+  using nsINode::SetOn##name_;                       \
+  mozilla::dom::EventHandlerNonNull* GetOn##name_(); \
+  void SetOn##name_(mozilla::dom::EventHandlerNonNull* handler);
+#define ERROR_EVENT(name_, id_, type_, struct_)                       \
+  using nsINode::GetOn##name_;                                        \
+  using nsINode::SetOn##name_;                                        \
+  already_AddRefed<mozilla::dom::EventHandlerNonNull> GetOn##name_(); \
+  void SetOn##name_(mozilla::dom::EventHandlerNonNull* handler);
+#include "mozilla/EventNameList.h"  // IWYU pragma: keep
+#undef ERROR_EVENT
+#undef FORWARDED_EVENT
+#undef EVENT
+  mozilla::dom::Element* GetOffsetParent() {
+    mozilla::CSSIntRect rcFrame;
+    return GetOffsetRect(rcFrame);
+  }
+  int32_t OffsetTop() {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.y;
+  }
+  int32_t OffsetLeft() {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.x;
+  }
+  int32_t OffsetWidth() {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.Width();
+  }
+  int32_t OffsetHeight() {
+    mozilla::CSSIntRect rcFrame;
+    GetOffsetRect(rcFrame);
+
+    return rcFrame.Height();
+  }
+
+  // These methods are already implemented in nsIContent but we want something
+  // faster for HTMLElements ignoring the namespace checking.
+  // This is safe because we already know that we are in the HTML namespace.
+  inline bool IsHTMLElement() const { return true; }
+
+  inline bool IsHTMLElement(nsAtom* aTag) const {
+    return mNodeInfo->Equals(aTag);
+  }
+
+  template <typename First, typename... Args>
+  inline bool IsAnyOfHTMLElements(First aFirst, Args... aArgs) const {
+    return IsNodeInternal(aFirst, aArgs...);
+  }
+
+  // https://html.spec.whatwg.org/multipage/custom-elements.html#dom-attachinternals
+  virtual already_AddRefed<mozilla::dom::ElementInternals> AttachInternals(
+      ErrorResult& aRv);
+
+  mozilla::dom::ElementInternals* GetInternals() const;
+
+  bool IsFormAssociatedCustomElements() const;
+
+  // Returns true if the event should not be handled from GetEventTargetParent.
+  virtual bool IsDisabledForEvents(mozilla::WidgetEvent* aEvent) {
+    return false;
+  }
+
+  bool Autofocus() const { return GetBoolAttr(nsGkAtoms::autofocus); }
+  void SetAutofocus(bool aVal, ErrorResult& aRv) {
+    SetHTMLBoolAttr(nsGkAtoms::autofocus, aVal, aRv);
+  }
+
+ protected:
+  virtual ~nsGenericHTMLElement() = default;
+
+ public:
+  // Implementation for nsIContent
+  nsresult BindToTree(BindContext&, nsINode& aParent) override;
+  void UnbindFromTree(bool aNullParent = true) override;
+
+  bool IsFocusableInternal(int32_t* aTabIndex, bool aWithMouse) override {
+    bool isFocusable = false;
+    IsHTMLFocusable(aWithMouse, &isFocusable, aTabIndex);
+    return isFocusable;
+  }
+  /**
+   * Returns true if a subclass is not allowed to override the value returned
+   * in aIsFocusable.
+   */
+  virtual bool IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
+                               int32_t* aTabIndex);
+  MOZ_CAN_RUN_SCRIPT
+  mozilla::Result<bool, nsresult> PerformAccesskey(
+      bool aKeyCausesActivation, bool aIsTrustedEvent) override;
+
+  /**
+   * Check if an event for an anchor can be handled
+   * @return true if the event can be handled, false otherwise
+   */
+  bool CheckHandleEventForAnchorsPreconditions(
+      mozilla::EventChainVisitor& aVisitor);
+  void GetEventTargetParentForAnchors(mozilla::EventChainPreVisitor& aVisitor);
+  MOZ_CAN_RUN_SCRIPT
+  nsresult PostHandleEventForAnchors(mozilla::EventChainPostVisitor& aVisitor);
+  bool IsHTMLLink(nsIURI** aURI) const;
+
+  // HTML element methods
+  void Compact() { mAttrs.Compact(); }
+
+  void UpdateEditableState(bool aNotify) override;
+
+  mozilla::dom::ElementState IntrinsicState() const override;
+
+  // Helper for setting our editable flag and notifying
+  void DoSetEditableFlag(bool aEditable, bool aNotify) {
+    SetEditableFlag(aEditable);
+    UpdateState(aNotify);
+  }
+
+  bool ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+                      const nsAString& aValue,
+                      nsIPrincipal* aMaybeScriptedPrincipal,
+                      nsAttrValue& aResult) override;
+
+  bool ParseBackgroundAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+                                const nsAString& aValue, nsAttrValue& aResult);
+
+  NS_IMETHOD_(bool) IsAttributeMapped(const nsAtom* aAttribute) const override;
+  nsMapRuleToAttributesFunc GetAttributeMappingFunction() const override;
+
+  /**
+   * Get the base target for any links within this piece
+   * of content. Generally, this is the document's base target,
+   * but certain content carries a local base for backward
+   * compatibility.
+   *
+   * @param aBaseTarget the base target [OUT]
+   */
+  void GetBaseTarget(nsAString& aBaseTarget) const;
+
+  /**
+   * Get the primary form control frame for this element.  Same as
+   * GetPrimaryFrame(), except it QI's to nsIFormControlFrame.
+   *
+   * @param aFlush whether to flush out frames so that they're up to date.
+   * @return the primary frame as nsIFormControlFrame
+   */
+  nsIFormControlFrame* GetFormControlFrame(bool aFlushFrames);
+
+  //----------------------------------------
+
+  /**
+   * Parse an alignment attribute (top/middle/bottom/baseline)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseAlignValue(const nsAString& aString, nsAttrValue& aResult);
+
+  /**
+   * Parse a div align string to value (left/right/center/middle/justify)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseDivAlignValue(const nsAString& aString,
+                                 nsAttrValue& aResult);
+
+  /**
+   * Convert a table halign string to value (left/right/center/char/justify)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableHAlignValue(const nsAString& aString,
+                                    nsAttrValue& aResult);
+
+  /**
+   * Convert a table cell halign string to value
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableCellHAlignValue(const nsAString& aString,
+                                        nsAttrValue& aResult);
+
+  /**
+   * Convert a table valign string to value (left/right/center/char/justify/
+   * abscenter/absmiddle/middle)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseTableVAlignValue(const nsAString& aString,
+                                    nsAttrValue& aResult);
+
+  /**
+   * Convert an image attribute to value (width, height, hspace, vspace, border)
+   *
+   * @param aAttribute the attribute to parse
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseImageAttribute(nsAtom* aAttribute, const nsAString& aString,
+                                  nsAttrValue& aResult);
+
+  static bool ParseReferrerAttribute(const nsAString& aString,
+                                     nsAttrValue& aResult);
+
+  /**
+   * Convert a frameborder string to value (yes/no/1/0)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseFrameborderValue(const nsAString& aString,
+                                    nsAttrValue& aResult);
+
+  /**
+   * Convert a scrolling string to value (yes/no/on/off/scroll/noscroll/auto)
+   *
+   * @param aString the string to parse
+   * @param aResult the resulting HTMLValue
+   * @return whether the value was parsed
+   */
+  static bool ParseScrollingValue(const nsAString& aString,
+                                  nsAttrValue& aResult);
+
+  /*
+   * Attribute Mapping Helpers
+   */
+
+  /**
+   * A style attribute mapping function for the most common attributes, to be
+   * called by subclasses' attribute mapping functions.  Currently handles
+   * dir, lang and hidden, could handle others.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapCommonAttributesInto(const nsMappedAttributes* aAttributes,
+                                      mozilla::MappedDeclarations&);
+  /**
+   * Same as MapCommonAttributesInto except that it does not handle hidden.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapCommonAttributesIntoExceptHidden(
+      const nsMappedAttributes* aAttributes, mozilla::MappedDeclarations&);
+
+  static const MappedAttributeEntry sCommonAttributeMap[];
+  static const MappedAttributeEntry sImageMarginSizeAttributeMap[];
+  static const MappedAttributeEntry sImageBorderAttributeMap[];
+  static const MappedAttributeEntry sImageAlignAttributeMap[];
+  static const MappedAttributeEntry sDivAlignAttributeMap[];
+  static const MappedAttributeEntry sBackgroundAttributeMap[];
+  static const MappedAttributeEntry sBackgroundColorAttributeMap[];
+
+  /**
+   * Helper to map the align attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageAlignAttributeInto(const nsMappedAttributes* aAttributes,
+                                         mozilla::MappedDeclarations&);
+
+  /**
+   * Helper to map the align attribute into a style struct for things
+   * like <div>, <h1>, etc.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapDivAlignAttributeInto(const nsMappedAttributes* aAttributes,
+                                       mozilla::MappedDeclarations&);
+
+  /**
+   * Helper to map the valign attribute into a style struct for things
+   * like <col>, <tr>, <section>, etc.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapVAlignAttributeInto(const nsMappedAttributes* aAttributes,
+                                     mozilla::MappedDeclarations&);
+
+  /**
+   * Helper to map the image border attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageBorderAttributeInto(const nsMappedAttributes* aAttributes,
+                                          mozilla::MappedDeclarations&);
+  /**
+   * Helper to map the image margin attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapImageMarginAttributeInto(const nsMappedAttributes* aAttributes,
+                                          mozilla::MappedDeclarations&);
+
+  // Whether to map the width and height attributes to aspect-ratio.
+  enum class MapAspectRatio { No, Yes };
+
+  /**
+   * Helper to map the image position attribute into a style struct.
+   */
+  static void MapImageSizeAttributesInto(const nsMappedAttributes*,
+                                         mozilla::MappedDeclarations&,
+                                         MapAspectRatio = MapAspectRatio::No);
+  /**
+   * Helper to map the iamge source attributes into a style stuct.
+   * Note:
+   * This will override the declaration created by the presentation attributes
+   * of HTMLImageElement (i.e. mapped by MapImageSizeAttributeInto).
+   * https://html.spec.whatwg.org/multipage/embedded-content.html#the-source-element
+   */
+  static void MapPictureSourceSizeAttributesInto(const nsMappedAttributes*,
+                                                 mozilla::MappedDeclarations&);
+
+  /**
+   * Helper to map the width and height attributes into the aspect-ratio
+   * property.
+   *
+   * If you also map the width/height attributes to width/height (as you should
+   * for any HTML element that isn't <canvas>) then you should use
+   * MapImageSizeAttributesInto instead, passing MapAspectRatio::Yes instead, as
+   * that'd be faster.
+   */
+  static void MapAspectRatioInto(const nsMappedAttributes*,
+                                 mozilla::MappedDeclarations&);
+
+  /**
+   * Helper to map `width` attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapWidthAttributeInto(const nsMappedAttributes* aAttributes,
+                                    mozilla::MappedDeclarations&);
+  /**
+   * Helper to map `height` attribute into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapHeightAttributeInto(const nsMappedAttributes* aAttributes,
+                                     mozilla::MappedDeclarations&);
+  /**
+   * Helper to map the background attribute
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBackgroundInto(const nsMappedAttributes* aAttributes,
+                                mozilla::MappedDeclarations&);
+  /**
+   * Helper to map the bgcolor attribute
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBGColorInto(const nsMappedAttributes* aAttributes,
+                             mozilla::MappedDeclarations&);
+  /**
+   * Helper to map the background attributes (currently background and bgcolor)
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapBackgroundAttributesInto(const nsMappedAttributes* aAttributes,
+                                          mozilla::MappedDeclarations&);
+  /**
+   * Helper to map the scrolling attribute on FRAME and IFRAME
+   * into a style struct.
+   *
+   * @param aAttributes the list of attributes to map
+   * @param aData the returned rule data [INOUT]
+   * @see GetAttributeMappingFunction
+   */
+  static void MapScrollingAttributeInto(const nsMappedAttributes* aAttributes,
+                                        mozilla::MappedDeclarations&);
+
+  // Form Helper Routines
+  /**
+   * Find an ancestor of this content node which is a form (could be null)
+   * @param aCurrentForm the current form for this node.  If this is
+   *        non-null, and no ancestor form is found, and the current form is in
+   *        a connected subtree with the node, the current form will be
+   *        returned.  This is needed to handle cases when HTML elements have a
+   *        current form that they're not descendants of.
+   * @note This method should not be called if the element has a form attribute.
+   */
+  mozilla::dom::HTMLFormElement* FindAncestorForm(
+      mozilla::dom::HTMLFormElement* aCurrentForm = nullptr);
+
+  /**
+   * See if the document being tested has nav-quirks mode enabled.
+   * @param doc the document
+   */
+  static bool InNavQuirksMode(Document*);
+
+  /**
+   * Gets the absolute URI value of an attribute, by resolving any relative
+   * URIs in the attribute against the baseuri of the element. If the attribute
+   * isn't a relative URI the value of the attribute is returned as is. Only
+   * works for attributes in null namespace.
+   *
+   * @param aAttr      name of attribute.
+   * @param aBaseAttr  name of base attribute.
+   * @param aResult    result value [out]
+   */
+  void GetURIAttr(nsAtom* aAttr, nsAtom* aBaseAttr, nsAString& aResult) const;
+
+  /**
+   * Gets the absolute URI values of an attribute, by resolving any relative
+   * URIs in the attribute against the baseuri of the element. If a substring
+   * isn't a relative URI, the substring is returned as is. Only works for
+   * attributes in null namespace.
+   */
+  bool GetURIAttr(nsAtom* aAttr, nsAtom* aBaseAttr, nsIURI** aURI) const;
+
+  bool IsHidden() const {
+    return HasAttr(kNameSpaceID_None, nsGkAtoms::hidden);
+  }
+
+  bool IsLabelable() const override;
+
+  static bool MatchLabelsElement(Element* aElement, int32_t aNamespaceID,
+                                 nsAtom* aAtom, void* aData);
+
+  already_AddRefed<nsINodeList> Labels();
+
+  static bool LegacyTouchAPIEnabled(JSContext* aCx, JSObject* aObj);
+
+  static inline bool CanHaveName(nsAtom* aTag) {
+    return aTag == nsGkAtoms::img || aTag == nsGkAtoms::form ||
+           aTag == nsGkAtoms::embed || aTag == nsGkAtoms::object;
+  }
+  static inline bool ShouldExposeNameAsHTMLDocumentProperty(Element* aElement) {
+    return aElement->IsHTMLElement() &&
+           CanHaveName(aElement->NodeInfo()->NameAtom());
+  }
+  static inline bool ShouldExposeIdAsHTMLDocumentProperty(Element* aElement) {
+    if (aElement->IsHTMLElement(nsGkAtoms::object)) {
+      return true;
+    }
+
+    // Per spec, <img> is exposed by id only if it also has a nonempty
+    // name (which doesn't have to match the id or anything).
+    // HasName() is true precisely when name is nonempty.
+    return aElement->IsHTMLElement(nsGkAtoms::img) && aElement->HasName();
+  }
+
+  virtual inline void ResultForDialogSubmit(nsAString& aResult) {
+    GetAttr(kNameSpaceID_None, nsGkAtoms::value, aResult);
+  }
+
+ protected:
+  /**
+   * Add/remove this element to the documents name cache
+   */
+  void AddToNameTable(nsAtom* aName);
+  void RemoveFromNameTable();
+
+  /**
+   * Register or unregister an access key to this element based on the
+   * accesskey attribute.
+   */
+  void RegUnRegAccessKey(bool aDoReg) override {
+    if (!HasFlag(NODE_HAS_ACCESSKEY)) {
+      return;
+    }
+
+    nsStyledElement::RegUnRegAccessKey(aDoReg);
+  }
+
+ protected:
+  void BeforeSetAttr(int32_t aNamespaceID, nsAtom* aName,
+                     const nsAttrValue* aValue, bool aNotify) override;
+  // TODO: Convert AfterSetAttr to MOZ_CAN_RUN_SCRIPT and get rid of
+  // kungFuDeathGrip in it.
+  MOZ_CAN_RUN_SCRIPT_BOUNDARY void AfterSetAttr(
+      int32_t aNamespaceID, nsAtom* aName, const nsAttrValue* aValue,
+      const nsAttrValue* aOldValue, nsIPrincipal* aMaybeScriptedPrincipal,
+      bool aNotify) override;
+
+  MOZ_CAN_RUN_SCRIPT void AfterSetPopoverAttr();
+
+  mozilla::EventListenerManager* GetEventListenerManagerForAttr(
+      nsAtom* aAttrName, bool* aDefer) override;
+
+  /**
+   * Handles dispatching a simulated click on `this` on space or enter.
+   * TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230)
+   */
+  MOZ_CAN_RUN_SCRIPT_BOUNDARY void HandleKeyboardActivation(
+      mozilla::EventChainPostVisitor&);
+
+  /** Dispatch a simulated mouse click by keyboard to the given element. */
+  MOZ_CAN_RUN_SCRIPT static nsresult DispatchSimulatedClick(
+      nsGenericHTMLElement* aElement, bool aIsTrusted,
+      nsPresContext* aPresContext);
+
+  /**
+   * Create a URI for the given aURISpec string.
+   * Returns INVALID_STATE_ERR and nulls *aURI if aURISpec is empty
+   * and the document's URI matches the element's base URI.
+   */
+  nsresult NewURIFromString(const nsAString& aURISpec, nsIURI** aURI);
+
+  void GetHTMLAttr(nsAtom* aName, nsAString& aResult) const {
+    GetAttr(aName, aResult);
+  }
+  void GetHTMLAttr(nsAtom* aName, mozilla::dom::DOMString& aResult) const {
+    GetAttr(kNameSpaceID_None, aName, aResult);
+  }
+  void GetHTMLEnumAttr(nsAtom* aName, nsAString& aResult) const {
+    GetEnumAttr(aName, nullptr, aResult);
+  }
+  void GetHTMLURIAttr(nsAtom* aName, nsAString& aResult) const {
+    GetURIAttr(aName, nullptr, aResult);
+  }
+
+  void SetHTMLAttr(nsAtom* aName, const nsAString& aValue) {
+    SetAttr(kNameSpaceID_None, aName, aValue, true);
+  }
+  void SetHTMLAttr(nsAtom* aName, const nsAString& aValue,
+                   mozilla::ErrorResult& aError) {
+    SetAttr(aName, aValue, aError);
+  }
+  void SetHTMLAttr(nsAtom* aName, const nsAString& aValue,
+                   nsIPrincipal* aTriggeringPrincipal,
+                   mozilla::ErrorResult& aError) {
+    SetAttr(aName, aValue, aTriggeringPrincipal, aError);
+  }
+  void UnsetHTMLAttr(nsAtom* aName, mozilla::ErrorResult& aError) {
+    UnsetAttr(aName, aError);
+  }
+  void SetHTMLBoolAttr(nsAtom* aName, bool aValue,
+                       mozilla::ErrorResult& aError) {
+    if (aValue) {
+      SetHTMLAttr(aName, u""_ns, aError);
+    } else {
+      UnsetHTMLAttr(aName, aError);
+    }
+  }
+  template <typename T>
+  void SetHTMLIntAttr(nsAtom* aName, T aValue, mozilla::ErrorResult& aError) {
+    nsAutoString value;
+    value.AppendInt(aValue);
+
+    SetHTMLAttr(aName, value, aError);
+  }
+
+  /**
+   * Gets the integer-value of an attribute, returns specified default value
+   * if the attribute isn't set or isn't set to an integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   */
+  int32_t GetIntAttr(nsAtom* aAttr, int32_t aDefault) const;
+
+  /**
+   * Sets value of attribute to specified integer. Only works for attributes
+   * in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Integer value of attribute.
+   */
+  nsresult SetIntAttr(nsAtom* aAttr, int32_t aValue);
+
+  /**
+   * Gets the unsigned integer-value of an attribute, returns specified default
+   * value if the attribute isn't set or isn't set to an integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   */
+  uint32_t GetUnsignedIntAttr(nsAtom* aAttr, uint32_t aDefault) const;
+
+  /**
+   * Sets value of attribute to specified unsigned integer. Only works for
+   * attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Integer value of attribute.
+   * @param aDefault Default value (in case value is out of range).  If the spec
+   *                 doesn't provide one, should be 1 if the value is limited to
+   *                 nonzero values, and 0 otherwise.
+   */
+  void SetUnsignedIntAttr(nsAtom* aName, uint32_t aValue, uint32_t aDefault,
+                          mozilla::ErrorResult& aError) {
+    nsAutoString value;
+    if (aValue > INT32_MAX) {
+      value.AppendInt(aDefault);
+    } else {
+      value.AppendInt(aValue);
+    }
+
+    SetHTMLAttr(aName, value, aError);
+  }
+
+  /**
+   * Gets the unsigned integer-value of an attribute that is stored as a
+   * dimension (i.e. could be an integer or a percentage), returns specified
+   * default value if the attribute isn't set or isn't set to a dimension. Only
+   * works for attributes in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aDefault default-value to return if attribute isn't set.
+   */
+  uint32_t GetDimensionAttrAsUnsignedInt(nsAtom* aAttr,
+                                         uint32_t aDefault) const;
+
+  /**
+   * Sets value of attribute to specified double. Only works for attributes
+   * in null namespace.
+   *
+   * @param aAttr    name of attribute.
+   * @param aValue   Double value of attribute.
+   */
+  void SetDoubleAttr(nsAtom* aAttr, double aValue, mozilla::ErrorResult& aRv) {
+    nsAutoString value;
+    value.AppendFloat(aValue);
+
+    SetHTMLAttr(aAttr, value, aRv);
+  }
+
+  /**
+   * Locates the EditorBase associated with this node.  In general this is
+   * equivalent to GetEditorInternal(), but for designmode or contenteditable,
+   * this may need to get an editor that's not actually on this element's
+   * associated TextControlFrame.  This is used by the spellchecking routines
+   * to get the editor affected by changing the spellcheck attribute on this
+   * node.
+   */
+  virtual already_AddRefed<mozilla::EditorBase> GetAssociatedEditor();
+
+  /**
+   * Get the frame's offset information for offsetTop/Left/Width/Height.
+   * Returns the parent the offset is relative to.
+   * @note This method flushes pending notifications (FlushType::Layout).
+   * @param aRect the offset information [OUT]
+   */
+  mozilla::dom::Element* GetOffsetRect(mozilla::CSSIntRect& aRect);
+
+  /**
+   * Ensures all editors associated with a subtree are synced, for purposes of
+   * spellchecking.
+   */
+  static void SyncEditorsOnSubtree(nsIContent* content);
+
+  enum ContentEditableTristate { eInherit = -1, eFalse = 0, eTrue = 1 };
+
+  /**
+   * Returns eTrue if the element has a contentEditable attribute and its value
+   * is "true" or an empty string. Returns eFalse if the element has a
+   * contentEditable attribute and its value is "false". Otherwise returns
+   * eInherit.
+   */
+  ContentEditableTristate GetContentEditableValue() const {
+    static const Element::AttrValuesArray values[] = {
+        nsGkAtoms::_false, nsGkAtoms::_true, nsGkAtoms::_empty, nullptr};
+
+    if (!MayHaveContentEditableAttr()) return eInherit;
+
+    int32_t value = FindAttrValueIn(
+        kNameSpaceID_None, nsGkAtoms::contenteditable, values, eIgnoreCase);
+
+    return value > 0 ? eTrue : (value == 0 ? eFalse : eInherit);
+  }
+
+  // Used by A, AREA, LINK, and STYLE.
+  already_AddRefed<nsIURI> GetHrefURIForAnchors() const;
+
+ public:
+  /**
+   * Returns whether this element is an editable root. There are two types of
+   * editable roots:
+   *   1) the documentElement if the whole document is editable (for example for
+   *      desginMode=on)
+   *   2) an element that is marked editable with contentEditable=true and that
+   *      doesn't have a parent or whose parent is not editable.
+   * Note that this doesn't return input and textarea elements that haven't been
+   * made editable through contentEditable or designMode.
+   */
+  bool IsEditableRoot() const;
+
+ private:
+  void ChangeEditableState(int32_t aChange);
+};
+
+namespace mozilla::dom {
+class HTMLFieldSetElement;
+}  // namespace mozilla::dom
+
+#define HTML_ELEMENT_FLAG_BIT(n_) \
+  NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
+
+// HTMLElement specific bits
+enum {
+  // Used to handle keyboard activation.
+  HTML_ELEMENT_ACTIVE_FOR_KEYBOARD = HTML_ELEMENT_FLAG_BIT(0),
+
+  // Remaining bits are type specific.
+  HTML_ELEMENT_TYPE_SPECIFIC_BITS_OFFSET =
+      ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + 1,
+};
+
+ASSERT_NODE_FLAGS_SPACE(HTML_ELEMENT_TYPE_SPECIFIC_BITS_OFFSET);
+
+#define FORM_ELEMENT_FLAG_BIT(n_) \
+  NODE_FLAG_BIT(HTML_ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
+
+// Form element specific bits
+enum {
+  // If this flag is set on an nsGenericHTMLFormElement or an HTMLImageElement,
+  // that means that we have added ourselves to our mForm.  It's possible to
+  // have a non-null mForm, but not have this flag set.  That happens when the
+  // form is set via the content sink.
+  ADDED_TO_FORM = FORM_ELEMENT_FLAG_BIT(0),
+
+  // If this flag is set on an nsGenericHTMLFormElement or an HTMLImageElement,
+  // that means that its form is in the process of being unbound from the tree,
+  // and this form element hasn't re-found its form in
+  // nsGenericHTMLFormElement::UnbindFromTree yet.
+  MAYBE_ORPHAN_FORM_ELEMENT = FORM_ELEMENT_FLAG_BIT(1),
+
+  // If this flag is set on an nsGenericHTMLElement or an HTMLImageElement, then
+  // the element might be in the past names map of its form.
+  MAY_BE_IN_PAST_NAMES_MAP = FORM_ELEMENT_FLAG_BIT(2)
+};
+
+// NOTE: I don't think it's possible to have both ADDED_TO_FORM and
+// MAYBE_ORPHAN_FORM_ELEMENT set at the same time, so if it becomes an issue we
+// can probably merge them into the same bit.  --bz
+
+ASSERT_NODE_FLAGS_SPACE(HTML_ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + 3);
+
+#undef FORM_ELEMENT_FLAG_BIT
+
+/**
+ * A helper class for form elements that can contain children
+ */
+class nsGenericHTMLFormElement : public nsGenericHTMLElement {
+ public:
+  nsGenericHTMLFormElement(
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo);
+
+  // nsIContent
+  nsresult BindToTree(BindContext&, nsINode& aParent) override;
+  void UnbindFromTree(bool aNullParent = true) override;
+
+  /**
+   * This callback is called by a fieldest on all its elements whenever its
+   * disabled attribute is changed so the element knows its disabled state
+   * might have changed.
+   *
+   * @note Classes redefining this method should not do any content
+   * state updates themselves but should just make sure to call into
+   * nsGenericHTMLFormElement::FieldSetDisabledChanged.
+   */
+  virtual void FieldSetDisabledChanged(bool aNotify);
+
+  void FieldSetFirstLegendChanged(bool aNotify) { UpdateFieldSet(aNotify); }
+
+  /**
+   * This callback is called by a fieldset on all it's elements when it's being
+   * destroyed. When called, the elements should check that aFieldset is there
+   * first parent fieldset and null mFieldset in that case only.
+   *
+   * @param aFieldSet The fieldset being removed.
+   */
+  void ForgetFieldSet(nsIContent* aFieldset);
+
+  void ClearForm(bool aRemoveFromForm, bool aUnbindOrDelete);
+
+ protected:
+  virtual ~nsGenericHTMLFormElement() = default;
+
+  void BeforeSetAttr(int32_t aNamespaceID, nsAtom* aName,
+                     const nsAttrValue* aValue, bool aNotify) override;
+
+  void AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
+                    const nsAttrValue* aValue, const nsAttrValue* aOldValue,
+                    nsIPrincipal* aMaybeScriptedPrincipal,
+                    bool aNotify) override;
+
+  virtual void BeforeSetForm(mozilla::dom::HTMLFormElement* aForm,
+                             bool aBindToTree) {}
+
+  virtual void AfterClearForm(bool aUnbindOrDelete) {}
+
+  /**
+   * Check our disabled content attribute and fieldset's (if it exists) disabled
+   * state to decide whether our disabled flag should be toggled.
+   */
+  virtual void UpdateDisabledState(bool aNotify);
+
+  virtual void SetFormInternal(mozilla::dom::HTMLFormElement* aForm,
+                               bool aBindToTree) {}
+
+  virtual mozilla::dom::HTMLFormElement* GetFormInternal() const {
+    return nullptr;
+  }
+
+  virtual mozilla::dom::HTMLFieldSetElement* GetFieldSetInternal() const {
+    return nullptr;
+  }
+
+  virtual void SetFieldSetInternal(
+      mozilla::dom::HTMLFieldSetElement* aFieldset) {}
+
+  /**
+   * This method will update the form owner, using @form or looking to a parent.
+   *
+   * @param aBindToTree Whether the element is being attached to the tree.
+   * @param aFormIdElement The element associated with the id in @form. If
+   * aBindToTree is false, aFormIdElement *must* contain the element associated
+   * with the id in @form. Otherwise, it *must* be null.
+   *
+   * @note Callers of UpdateFormOwner have to be sure the element is in a
+   * document (GetUncomposedDoc() != nullptr).
+   */
+  virtual void UpdateFormOwner(bool aBindToTree, Element* aFormIdElement);
+
+  /**
+   * This method will update mFieldset and set it to the first fieldset parent.
+   */
+  void UpdateFieldSet(bool aNotify);
+
+  /**
+   * Add a form id observer which will observe when the element with the id in
+   * @form will change.
+   *
+   * @return The element associated with the current id in @form (may be null).
+   */
+  Element* AddFormIdObserver();
+
+  /**
+   * Remove the form id observer.
+   */
+  void RemoveFormIdObserver();
+
+  /**
+   * This method is a a callback for IDTargetObserver (from Document).
+   * It will be called each time the element associated with the id in @form
+   * changes.
+   */
+  static bool FormIdUpdated(Element* aOldElement, Element* aNewElement,
+                            void* aData);
+
+  // Returns true if the event should not be handled from GetEventTargetParent
+  bool IsElementDisabledForEvents(mozilla::WidgetEvent* aEvent,
+                                  nsIFrame* aFrame);
+
+  /**
+   * Returns if the control can be disabled.
+   */
+  virtual bool CanBeDisabled() const { return false; }
+
+  /**
+   * Returns if the readonly attribute applies.
+   */
+  virtual bool DoesReadOnlyApply() const { return false; }
+
+  /**
+   *  Returns true if the element is a form associated element.
+   *  See https://html.spec.whatwg.org/#form-associated-element.
+   */
+  virtual bool IsFormAssociatedElement() const { return false; }
+};
+
+class nsGenericHTMLFormControlElement : public nsGenericHTMLFormElement,
+                                        public nsIFormControl {
+ public:
+  nsGenericHTMLFormControlElement(
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, FormControlType);
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  NS_IMPL_FROMNODE_HELPER(nsGenericHTMLFormControlElement,
+                          IsHTMLFormControlElement())
+
+  // nsINode
+  nsINode* GetScopeChainParent() const override;
+  bool IsHTMLFormControlElement() const final { return true; }
+
+  // nsIContent
+  void SaveSubtreeState() override;
+  IMEState GetDesiredIMEState() override;
+  void UnbindFromTree(bool aNullParent = true) override;
+
+  // nsGenericHTMLElement
+  // autocapitalize attribute support
+  void GetAutocapitalize(nsAString& aValue) const override;
+  bool IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
+                       int32_t* aTabIndex) override;
+
+  // EventTarget
+  void GetEventTargetParent(mozilla::EventChainPreVisitor& aVisitor) override;
+  nsresult PreHandleEvent(mozilla::EventChainVisitor& aVisitor) override;
+
+  // nsIFormControl
+  mozilla::dom::HTMLFieldSetElement* GetFieldSet() override;
+  mozilla::dom::HTMLFormElement* GetForm() const override { return mForm; }
+  void SetForm(mozilla::dom::HTMLFormElement* aForm) override;
+  void ClearForm(bool aRemoveFromForm, bool aUnbindOrDelete) override;
+  bool AllowDrop() override { return true; }
+
+ protected:
+  virtual ~nsGenericHTMLFormControlElement();
+
+  // Element
+  mozilla::dom::ElementState IntrinsicState() const override;
+  bool IsLabelable() const override;
+
+  // nsGenericHTMLFormElement
+  bool CanBeDisabled() const override;
+  bool DoesReadOnlyApply() const override;
+  void SetFormInternal(mozilla::dom::HTMLFormElement* aForm,
+                       bool aBindToTree) override;
+  mozilla::dom::HTMLFormElement* GetFormInternal() const override;
+  mozilla::dom::HTMLFieldSetElement* GetFieldSetInternal() const override;
+  void SetFieldSetInternal(
+      mozilla::dom::HTMLFieldSetElement* aFieldset) override;
+  bool IsFormAssociatedElement() const override { return true; }
+
+  /**
+   * Update our required/optional flags to match the given aIsRequired boolean.
+   */
+  void UpdateRequiredState(bool aIsRequired, bool aNotify);
+
+  bool IsAutocapitalizeInheriting() const;
+
+  /**
+   * Save to presentation state.  The form control will determine whether it
+   * has anything to save and if so, create an entry in the layout history for
+   * its pres context.
+   */
+  virtual void SaveState() {}
+
+  /** The form that contains this control */
+  mozilla::dom::HTMLFormElement* mForm;
+
+  /* This is a pointer to our closest fieldset parent if any */
+  mozilla::dom::HTMLFieldSetElement* mFieldSet;
+};
+
+enum class PopoverTargetAction : uint8_t {
+  Toggle,
+  Show,
+  Hide,
+};
+
+class nsGenericHTMLFormControlElementWithState
+    : public nsGenericHTMLFormControlElement {
+ public:
+  nsGenericHTMLFormControlElementWithState(
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
+      mozilla::dom::FromParser aFromParser, FormControlType);
+
+  bool IsGenericHTMLFormControlElementWithState() const final { return true; }
+  NS_IMPL_FROMNODE_HELPER(nsGenericHTMLFormControlElementWithState,
+                          IsGenericHTMLFormControlElementWithState())
+
+  // Element
+  bool ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+                      const nsAString& aValue,
+                      nsIPrincipal* aMaybeScriptedPrincipal,
+                      nsAttrValue& aResult) override;
+
+  // PopoverInvokerElement
+  mozilla::dom::Element* GetPopoverTargetElement() const;
+  void SetPopoverTargetElement(mozilla::dom::Element*);
+  void GetPopoverTargetAction(nsAString& aValue) const {
+    GetHTMLEnumAttr(nsGkAtoms::popovertargetaction, aValue);
+  }
+  void SetPopoverTargetAction(const nsAString& aValue) {
+    SetHTMLAttr(nsGkAtoms::popovertargetaction, aValue);
+  }
+
+  /**
+   * https://html.spec.whatwg.org/#popover-target-attribute-activation-behavior
+   */
+  MOZ_CAN_RUN_SCRIPT void HandlePopoverTargetAction();
+
+  /**
+   * Get the presentation state for a piece of content, or create it if it does
+   * not exist.  Generally used by SaveState().
+   */
+  mozilla::PresState* GetPrimaryPresState();
+
+  /**
+   * Get the layout history object for a particular piece of content.
+   *
+   * @param aRead if true, won't return a layout history state if the
+   *              layout history state is empty.
+   * @return the history state object
+   */
+  already_AddRefed<nsILayoutHistoryState> GetLayoutHistory(bool aRead);
+
+  /**
+   * Called when we have been cloned and adopted, and the information of the
+   * node has been changed.
+   */
+  void NodeInfoChanged(Document* aOldDoc) override;
+
+  void GetFormAction(nsString& aValue);
+
+ protected:
+  /**
+   * Restore from presentation state.  You pass in the presentation state for
+   * this form control (generated with GenerateStateKey() + "-C") and the form
+   * control will grab its state from there.
+   *
+   * @param aState the pres state to use to restore the control
+   * @return true if the form control was a checkbox and its
+   *         checked state was restored, false otherwise.
+   */
+  virtual bool RestoreState(mozilla::PresState* aState) { return false; }
+
+  /**
+   * Restore the state for a form control in response to the element being
+   * inserted into the document by the parser.  Ends up calling RestoreState().
+   *
+   * GenerateStateKey() must already have been called.
+   *
+   * @return false if RestoreState() was not called, the return
+   *         value of RestoreState() otherwise.
+   */
+  bool RestoreFormControlState();
+
+  /* Generates the state key for saving the form state in the session if not
+     computed already. The result is stored in mStateKey. */
+  void GenerateStateKey();
+
+  int32_t GetParserInsertedControlNumberForStateKey() const override {
+    return mControlNumber;
+  }
+
+  /* Used to store the key to that element in the session. Is void until
+     GenerateStateKey has been used */
+  nsCString mStateKey;
+
+  // A number for this form control that is unique within its owner document.
+  // This is only set to a number for elements inserted into the document by
+  // the parser from the network.  Otherwise, it is -1.
+  int32_t mControlNumber;
+};
+
+#define NS_INTERFACE_MAP_ENTRY_IF_TAG(_interface, _tag) \
+  NS_INTERFACE_MAP_ENTRY_CONDITIONAL(_interface,        \
+                                     mNodeInfo->Equals(nsGkAtoms::_tag))
+
+namespace mozilla::dom {
+
+using HTMLContentCreatorFunction =
+    nsGenericHTMLElement* (*)(already_AddRefed<mozilla::dom::NodeInfo>&&,
+                              mozilla::dom::FromParser);
+
+}  // namespace mozilla::dom
+
+/**
+ * A macro to declare the NS_NewHTMLXXXElement() functions.
+ */
+#define NS_DECLARE_NS_NEW_HTML_ELEMENT(_elementName)        \
+  namespace mozilla {                                       \
+  namespace dom {                                           \
+  class HTML##_elementName##Element;                        \
+  }                                                         \
+  }                                                         \
+  nsGenericHTMLElement* NS_NewHTML##_elementName##Element(  \
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
+      mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER);
+
+#define NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(_elementName)                \
+  inline nsGenericHTMLElement* NS_NewHTML##_elementName##Element(             \
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,                   \
+      mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER) { \
+    return NS_NewHTMLSharedElement(std::move(aNodeInfo), aFromParser);        \
+  }
+
+/**
+ * A macro to implement the NS_NewHTMLXXXElement() functions.
+ */
+#define NS_IMPL_NS_NEW_HTML_ELEMENT(_elementName)                     \
+  nsGenericHTMLElement* NS_NewHTML##_elementName##Element(            \
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,           \
+      mozilla::dom::FromParser aFromParser) {                         \
+    RefPtr<mozilla::dom::NodeInfo> nodeInfo(aNodeInfo);               \
+    auto* nim = nodeInfo->NodeInfoManager();                          \
+    MOZ_ASSERT(nim);                                                  \
+    return new (nim)                                                  \
+        mozilla::dom::HTML##_elementName##Element(nodeInfo.forget()); \
+  }
+
+#define NS_IMPL_NS_NEW_HTML_ELEMENT_CHECK_PARSER(_elementName)  \
+  nsGenericHTMLElement* NS_NewHTML##_elementName##Element(      \
+      already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,     \
+      mozilla::dom::FromParser aFromParser) {                   \
+    RefPtr<mozilla::dom::NodeInfo> nodeInfo(aNodeInfo);         \
+    auto* nim = nodeInfo->NodeInfoManager();                    \
+    MOZ_ASSERT(nim);                                            \
+    return new (nim) mozilla::dom::HTML##_elementName##Element( \
+        nodeInfo.forget(), aFromParser);                        \
+  }
+
+// Here, we expand 'NS_DECLARE_NS_NEW_HTML_ELEMENT()' by hand.
+// (Calling the macro directly (with no args) produces compiler warnings.)
+nsGenericHTMLElement* NS_NewHTMLElement(
+    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
+    mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER);
+
+// Distinct from the above in order to have function pointer that compared
+// unequal to a function pointer to the above.
+nsGenericHTMLElement* NS_NewCustomElement(
+    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
+    mozilla::dom::FromParser aFromParser = mozilla::dom::NOT_FROM_PARSER);
+
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Shared)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(SharedList)
+
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Anchor)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Area)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Audio)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(BR)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Body)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Button)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Canvas)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Content)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Mod)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Data)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(DataList)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Details)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Dialog)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Div)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Embed)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(FieldSet)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Font)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Form)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Frame)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(FrameSet)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(HR)
+NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(Head)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Heading)
+NS_DECLARE_NS_NEW_HTML_ELEMENT_AS_SHARED(Html)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(IFrame)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Image)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Input)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(LI)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Label)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Legend)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Link)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Marquee)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Map)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Menu)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Meta)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Meter)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Object)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(OptGroup)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Option)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Output)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Paragraph)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Picture)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Pre)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Progress)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Script)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Select)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Slot)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Source)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Span)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Style)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Summary)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCaption)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCell)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableCol)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Table)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableRow)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TableSection)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Tbody)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Template)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(TextArea)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Tfoot)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Thead)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Time)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Title)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Track)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Unknown)
+NS_DECLARE_NS_NEW_HTML_ELEMENT(Video)
+
+#endif /* nsGenericHTMLElement_h___ */