Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 1645 insertions, 0 deletions

diff --git a/dom/html/HTMLSelectElement.cpp b/dom/html/HTMLSelectElement.cpp
new file mode 100644
index 0000000000..18bf2b79b2
--- /dev/null
+++ b/dom/html/HTMLSelectElement.cpp
@@ -0,0 +1,1645 @@
+/* -*- 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/. */
+
+#include "mozilla/dom/HTMLSelectElement.h"
+
+#include "mozAutoDocUpdate.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/BasicEvents.h"
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/FormData.h"
+#include "mozilla/dom/HTMLOptGroupElement.h"
+#include "mozilla/dom/HTMLOptionElement.h"
+#include "mozilla/dom/HTMLSelectElementBinding.h"
+#include "mozilla/dom/UnionTypes.h"
+#include "mozilla/dom/WindowGlobalChild.h"
+#include "mozilla/MappedDeclarationsBuilder.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/Unused.h"
+#include "nsContentCreatorFunctions.h"
+#include "nsContentList.h"
+#include "nsContentUtils.h"
+#include "nsError.h"
+#include "nsGkAtoms.h"
+#include "nsComboboxControlFrame.h"
+#include "mozilla/dom/Document.h"
+#include "nsIFormControlFrame.h"
+#include "nsIFrame.h"
+#include "nsListControlFrame.h"
+#include "nsISelectControlFrame.h"
+#include "nsLayoutUtils.h"
+#include "mozilla/PresState.h"
+#include "nsServiceManagerUtils.h"
+#include "nsStyleConsts.h"
+#include "nsTextNode.h"
+
+NS_IMPL_NS_NEW_HTML_ELEMENT_CHECK_PARSER(Select)
+
+namespace mozilla::dom {
+
+//----------------------------------------------------------------------
+//
+// SafeOptionListMutation
+//
+
+SafeOptionListMutation::SafeOptionListMutation(nsIContent* aSelect,
+                                               nsIContent* aParent,
+                                               nsIContent* aKid,
+                                               uint32_t aIndex, bool aNotify)
+    : mSelect(HTMLSelectElement::FromNodeOrNull(aSelect)),
+      mTopLevelMutation(false),
+      mNeedsRebuild(false),
+      mNotify(aNotify) {
+  if (mSelect) {
+    mInitialSelectedOption = mSelect->Item(mSelect->SelectedIndex());
+    mTopLevelMutation = !mSelect->mMutating;
+    if (mTopLevelMutation) {
+      mSelect->mMutating = true;
+    } else {
+      // This is very unfortunate, but to handle mutation events properly,
+      // option list must be up-to-date before inserting or removing options.
+      // Fortunately this is called only if mutation event listener
+      // adds or removes options.
+      mSelect->RebuildOptionsArray(mNotify);
+    }
+    nsresult rv;
+    if (aKid) {
+      rv = mSelect->WillAddOptions(aKid, aParent, aIndex, mNotify);
+    } else {
+      rv = mSelect->WillRemoveOptions(aParent, aIndex, mNotify);
+    }
+    mNeedsRebuild = NS_FAILED(rv);
+  }
+}
+
+SafeOptionListMutation::~SafeOptionListMutation() {
+  if (mSelect) {
+    if (mNeedsRebuild || (mTopLevelMutation && mGuard.Mutated(1))) {
+      mSelect->RebuildOptionsArray(true);
+    }
+    if (mTopLevelMutation) {
+      mSelect->mMutating = false;
+    }
+    if (mSelect->Item(mSelect->SelectedIndex()) != mInitialSelectedOption) {
+      // We must have triggered the SelectSomething() codepath, which can cause
+      // our validity to change.  Unfortunately, our attempt to update validity
+      // in that case may not have worked correctly, because we actually call it
+      // before we have inserted the new <option>s into the DOM!  Go ahead and
+      // update validity here as needed, because by now we know our <option>s
+      // are where they should be.
+      mSelect->UpdateValueMissingValidityState();
+      mSelect->UpdateValidityElementStates(mNotify);
+    }
+#ifdef DEBUG
+    mSelect->VerifyOptionsArray();
+#endif
+  }
+}
+
+//----------------------------------------------------------------------
+//
+// HTMLSelectElement
+//
+
+// construction, destruction
+
+HTMLSelectElement::HTMLSelectElement(
+    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
+    FromParser aFromParser)
+    : nsGenericHTMLFormControlElementWithState(
+          std::move(aNodeInfo), aFromParser, FormControlType::Select),
+      mOptions(new HTMLOptionsCollection(this)),
+      mAutocompleteAttrState(nsContentUtils::eAutocompleteAttrState_Unknown),
+      mAutocompleteInfoState(nsContentUtils::eAutocompleteAttrState_Unknown),
+      mIsDoneAddingChildren(!aFromParser),
+      mDisabledChanged(false),
+      mMutating(false),
+      mInhibitStateRestoration(!!(aFromParser & FROM_PARSER_FRAGMENT)),
+      mUserInteracted(false),
+      mDefaultSelectionSet(false),
+      mIsOpenInParentProcess(false),
+      mNonOptionChildren(0),
+      mOptGroupCount(0),
+      mSelectedIndex(-1) {
+  SetHasWeirdParserInsertionMode();
+
+  // DoneAddingChildren() will be called later if it's from the parser,
+  // otherwise it is
+
+  // Set up our default state: enabled, optional, and valid.
+  AddStatesSilently(ElementState::ENABLED | ElementState::OPTIONAL_ |
+                    ElementState::VALID);
+}
+
+// ISupports
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(HTMLSelectElement)
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(
+    HTMLSelectElement, nsGenericHTMLFormControlElementWithState)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mValidity)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOptions)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSelectedOptions)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(
+    HTMLSelectElement, nsGenericHTMLFormControlElementWithState)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mValidity)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mSelectedOptions)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(
+    HTMLSelectElement, nsGenericHTMLFormControlElementWithState,
+    nsIConstraintValidation)
+
+// nsIDOMHTMLSelectElement
+
+NS_IMPL_ELEMENT_CLONE(HTMLSelectElement)
+
+void HTMLSelectElement::SetCustomValidity(const nsAString& aError) {
+  ConstraintValidation::SetCustomValidity(aError);
+  UpdateValidityElementStates(true);
+}
+
+// https://html.spec.whatwg.org/multipage/input.html#dom-input-showpicker
+void HTMLSelectElement::ShowPicker(ErrorResult& aRv) {
+  // Step 1. If this is not mutable, then throw an "InvalidStateError"
+  // DOMException.
+  if (IsDisabled()) {
+    return aRv.ThrowInvalidStateError("This select is disabled.");
+  }
+
+  // Step 2. If this's relevant settings object's origin is not same origin with
+  // this's relevant settings object's top-level origin, and this is a select
+  // element, [...], then throw a "SecurityError" DOMException.
+  nsPIDOMWindowInner* window = OwnerDoc()->GetInnerWindow();
+  WindowGlobalChild* windowGlobalChild =
+      window ? window->GetWindowGlobalChild() : nullptr;
+  if (!windowGlobalChild || !windowGlobalChild->SameOriginWithTop()) {
+    return aRv.ThrowSecurityError(
+        "Call was blocked because the current origin isn't same-origin with "
+        "top.");
+  }
+
+  // Step 3. If this's relevant global object does not have transient
+  // activation, then throw a "NotAllowedError" DOMException.
+  if (!OwnerDoc()->HasValidTransientUserGestureActivation()) {
+    return aRv.ThrowNotAllowedError(
+        "Call was blocked due to lack of user activation.");
+  }
+
+  // Step 4. If this is a select element, and this is not being rendered, then
+  // throw a "NotSupportedError" DOMException.
+
+  // Flush frames so that IsRendered returns up-to-date results.
+  Unused << GetPrimaryFrame(FlushType::Frames);
+  if (!IsRendered()) {
+    return aRv.ThrowNotSupportedError("This select isn't being rendered.");
+  }
+
+  // Step 5. Show the picker, if applicable, for this.
+#if !defined(ANDROID)
+  if (!IsCombobox()) {
+    return;
+  }
+#endif
+  if (!OpenInParentProcess()) {
+    RefPtr<Document> doc = OwnerDoc();
+    nsContentUtils::DispatchChromeEvent(doc, this, u"mozshowdropdown"_ns,
+                                        CanBubble::eYes, Cancelable::eNo);
+  }
+}
+
+void HTMLSelectElement::GetAutocomplete(DOMString& aValue) {
+  const nsAttrValue* attributeVal = GetParsedAttr(nsGkAtoms::autocomplete);
+
+  mAutocompleteAttrState = nsContentUtils::SerializeAutocompleteAttribute(
+      attributeVal, aValue, mAutocompleteAttrState);
+}
+
+void HTMLSelectElement::GetAutocompleteInfo(AutocompleteInfo& aInfo) {
+  const nsAttrValue* attributeVal = GetParsedAttr(nsGkAtoms::autocomplete);
+  mAutocompleteInfoState = nsContentUtils::SerializeAutocompleteAttribute(
+      attributeVal, aInfo, mAutocompleteInfoState, true);
+}
+
+void HTMLSelectElement::InsertChildBefore(nsIContent* aKid,
+                                          nsIContent* aBeforeThis, bool aNotify,
+                                          ErrorResult& aRv) {
+  const uint32_t index =
+      aBeforeThis ? *ComputeIndexOf(aBeforeThis) : GetChildCount();
+  SafeOptionListMutation safeMutation(this, this, aKid, index, aNotify);
+  nsGenericHTMLFormControlElementWithState::InsertChildBefore(aKid, aBeforeThis,
+                                                              aNotify, aRv);
+  if (aRv.Failed()) {
+    safeMutation.MutationFailed();
+  }
+}
+
+void HTMLSelectElement::RemoveChildNode(nsIContent* aKid, bool aNotify) {
+  SafeOptionListMutation safeMutation(this, this, nullptr,
+                                      *ComputeIndexOf(aKid), aNotify);
+  nsGenericHTMLFormControlElementWithState::RemoveChildNode(aKid, aNotify);
+}
+
+void HTMLSelectElement::InsertOptionsIntoList(nsIContent* aOptions,
+                                              int32_t aListIndex,
+                                              int32_t aDepth, bool aNotify) {
+  MOZ_ASSERT(aDepth == 0 || aDepth == 1);
+  int32_t insertIndex = aListIndex;
+
+  HTMLOptionElement* optElement = HTMLOptionElement::FromNode(aOptions);
+  if (optElement) {
+    mOptions->InsertOptionAt(optElement, insertIndex);
+    insertIndex++;
+  } else if (aDepth == 0) {
+    // If it's at the top level, then we just found out there are non-options
+    // at the top level, which will throw off the insert count
+    mNonOptionChildren++;
+
+    // Deal with optgroups
+    if (aOptions->IsHTMLElement(nsGkAtoms::optgroup)) {
+      mOptGroupCount++;
+
+      for (nsIContent* child = aOptions->GetFirstChild(); child;
+           child = child->GetNextSibling()) {
+        optElement = HTMLOptionElement::FromNode(child);
+        if (optElement) {
+          mOptions->InsertOptionAt(optElement, insertIndex);
+          insertIndex++;
+        }
+      }
+    }
+  }  // else ignore even if optgroup; we want to ignore nested optgroups.
+
+  // Deal with the selected list
+  if (insertIndex - aListIndex) {
+    // Fix the currently selected index
+    if (aListIndex <= mSelectedIndex) {
+      mSelectedIndex += (insertIndex - aListIndex);
+      OnSelectionChanged();
+    }
+
+    // Get the frame stuff for notification. No need to flush here
+    // since if there's no frame for the select yet the select will
+    // get into the right state once it's created.
+    nsISelectControlFrame* selectFrame = nullptr;
+    AutoWeakFrame weakSelectFrame;
+    bool didGetFrame = false;
+
+    // Actually select the options if the added options warrant it
+    for (int32_t i = aListIndex; i < insertIndex; i++) {
+      // Notify the frame that the option is added
+      if (!didGetFrame || (selectFrame && !weakSelectFrame.IsAlive())) {
+        selectFrame = GetSelectFrame();
+        weakSelectFrame = do_QueryFrame(selectFrame);
+        didGetFrame = true;
+      }
+
+      if (selectFrame) {
+        selectFrame->AddOption(i);
+      }
+
+      RefPtr<HTMLOptionElement> option = Item(i);
+      if (option && option->Selected()) {
+        // Clear all other options
+        if (!HasAttr(nsGkAtoms::multiple)) {
+          OptionFlags mask{OptionFlag::IsSelected, OptionFlag::ClearAll,
+                           OptionFlag::SetDisabled, OptionFlag::Notify,
+                           OptionFlag::InsertingOptions};
+          SetOptionsSelectedByIndex(i, i, mask);
+        }
+
+        // This is sort of a hack ... we need to notify that the option was
+        // set and change selectedIndex even though we didn't really change
+        // its value.
+        OnOptionSelected(selectFrame, i, true, false, aNotify);
+      }
+    }
+
+    CheckSelectSomething(aNotify);
+  }
+}
+
+nsresult HTMLSelectElement::RemoveOptionsFromList(nsIContent* aOptions,
+                                                  int32_t aListIndex,
+                                                  int32_t aDepth,
+                                                  bool aNotify) {
+  MOZ_ASSERT(aDepth == 0 || aDepth == 1);
+  int32_t numRemoved = 0;
+
+  HTMLOptionElement* optElement = HTMLOptionElement::FromNode(aOptions);
+  if (optElement) {
+    if (mOptions->ItemAsOption(aListIndex) != optElement) {
+      NS_ERROR("wrong option at index");
+      return NS_ERROR_UNEXPECTED;
+    }
+    mOptions->RemoveOptionAt(aListIndex);
+    numRemoved++;
+  } else if (aDepth == 0) {
+    // Yay, one less artifact at the top level.
+    mNonOptionChildren--;
+
+    // Recurse down deeper for options
+    if (mOptGroupCount && aOptions->IsHTMLElement(nsGkAtoms::optgroup)) {
+      mOptGroupCount--;
+
+      for (nsIContent* child = aOptions->GetFirstChild(); child;
+           child = child->GetNextSibling()) {
+        optElement = HTMLOptionElement::FromNode(child);
+        if (optElement) {
+          if (mOptions->ItemAsOption(aListIndex) != optElement) {
+            NS_ERROR("wrong option at index");
+            return NS_ERROR_UNEXPECTED;
+          }
+          mOptions->RemoveOptionAt(aListIndex);
+          numRemoved++;
+        }
+      }
+    }
+  }  // else don't check for an optgroup; we want to ignore nested optgroups
+
+  if (numRemoved) {
+    // Tell the widget we removed the options
+    nsISelectControlFrame* selectFrame = GetSelectFrame();
+    if (selectFrame) {
+      nsAutoScriptBlocker scriptBlocker;
+      for (int32_t i = aListIndex; i < aListIndex + numRemoved; ++i) {
+        selectFrame->RemoveOption(i);
+      }
+    }
+
+    // Fix the selected index
+    if (aListIndex <= mSelectedIndex) {
+      if (mSelectedIndex < (aListIndex + numRemoved)) {
+        // aListIndex <= mSelectedIndex < aListIndex+numRemoved
+        // Find a new selected index if it was one of the ones removed.
+        // If this is a Combobox, no other Item will be selected.
+        if (IsCombobox()) {
+          mSelectedIndex = -1;
+          OnSelectionChanged();
+        } else {
+          FindSelectedIndex(aListIndex, aNotify);
+        }
+      } else {
+        // Shift the selected index if something in front of it was removed
+        // aListIndex+numRemoved <= mSelectedIndex
+        mSelectedIndex -= numRemoved;
+        OnSelectionChanged();
+      }
+    }
+
+    // Select something in case we removed the selected option on a
+    // single select
+    if (!CheckSelectSomething(aNotify) && mSelectedIndex == -1) {
+      // Update the validity state in case of we've just removed the last
+      // option.
+      UpdateValueMissingValidityState();
+      UpdateValidityElementStates(aNotify);
+    }
+  }
+
+  return NS_OK;
+}
+
+// XXXldb Doing the processing before the content nodes have been added
+// to the document (as the name of this function seems to require, and
+// as the callers do), is highly unusual.  Passing around unparented
+// content to other parts of the app can make those things think the
+// options are the root content node.
+NS_IMETHODIMP
+HTMLSelectElement::WillAddOptions(nsIContent* aOptions, nsIContent* aParent,
+                                  int32_t aContentIndex, bool aNotify) {
+  if (this != aParent && this != aParent->GetParent()) {
+    return NS_OK;
+  }
+  int32_t level = aParent == this ? 0 : 1;
+
+  // Get the index where the options will be inserted
+  int32_t ind = -1;
+  if (!mNonOptionChildren) {
+    // If there are no artifacts, aContentIndex == ind
+    ind = aContentIndex;
+  } else {
+    // If there are artifacts, we have to get the index of the option the
+    // hard way
+    int32_t children = aParent->GetChildCount();
+
+    if (aContentIndex >= children) {
+      // If the content insert is after the end of the parent, then we want to
+      // get the next index *after* the parent and insert there.
+      ind = GetOptionIndexAfter(aParent);
+    } else {
+      // If the content insert is somewhere in the middle of the container, then
+      // we want to get the option currently at the index and insert in front of
+      // that.
+      nsIContent* currentKid = aParent->GetChildAt_Deprecated(aContentIndex);
+      NS_ASSERTION(currentKid, "Child not found!");
+      if (currentKid) {
+        ind = GetOptionIndexAt(currentKid);
+      } else {
+        ind = -1;
+      }
+    }
+  }
+
+  InsertOptionsIntoList(aOptions, ind, level, aNotify);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+HTMLSelectElement::WillRemoveOptions(nsIContent* aParent, int32_t aContentIndex,
+                                     bool aNotify) {
+  if (this != aParent && this != aParent->GetParent()) {
+    return NS_OK;
+  }
+  int32_t level = this == aParent ? 0 : 1;
+
+  // Get the index where the options will be removed
+  nsIContent* currentKid = aParent->GetChildAt_Deprecated(aContentIndex);
+  if (currentKid) {
+    int32_t ind;
+    if (!mNonOptionChildren) {
+      // If there are no artifacts, aContentIndex == ind
+      ind = aContentIndex;
+    } else {
+      // If there are artifacts, we have to get the index of the option the
+      // hard way
+      ind = GetFirstOptionIndex(currentKid);
+    }
+    if (ind != -1) {
+      nsresult rv = RemoveOptionsFromList(currentKid, ind, level, aNotify);
+      NS_ENSURE_SUCCESS(rv, rv);
+    }
+  }
+
+  return NS_OK;
+}
+
+int32_t HTMLSelectElement::GetOptionIndexAt(nsIContent* aOptions) {
+  // Search this node and below.
+  // If not found, find the first one *after* this node.
+  int32_t retval = GetFirstOptionIndex(aOptions);
+  if (retval == -1) {
+    retval = GetOptionIndexAfter(aOptions);
+  }
+
+  return retval;
+}
+
+int32_t HTMLSelectElement::GetOptionIndexAfter(nsIContent* aOptions) {
+  // - If this is the select, the next option is the last.
+  // - If not, search all the options after aOptions and up to the last option
+  //   in the parent.
+  // - If it's not there, search for the first option after the parent.
+  if (aOptions == this) {
+    return Length();
+  }
+
+  int32_t retval = -1;
+
+  nsCOMPtr<nsIContent> parent = aOptions->GetParent();
+
+  if (parent) {
+    const int32_t index = parent->ComputeIndexOf_Deprecated(aOptions);
+    const int32_t count = static_cast<int32_t>(parent->GetChildCount());
+
+    retval = GetFirstChildOptionIndex(parent, index + 1, count);
+
+    if (retval == -1) {
+      retval = GetOptionIndexAfter(parent);
+    }
+  }
+
+  return retval;
+}
+
+int32_t HTMLSelectElement::GetFirstOptionIndex(nsIContent* aOptions) {
+  int32_t listIndex = -1;
+  HTMLOptionElement* optElement = HTMLOptionElement::FromNode(aOptions);
+  if (optElement) {
+    mOptions->GetOptionIndex(optElement, 0, true, &listIndex);
+    return listIndex;
+  }
+
+  listIndex = GetFirstChildOptionIndex(aOptions, 0, aOptions->GetChildCount());
+
+  return listIndex;
+}
+
+int32_t HTMLSelectElement::GetFirstChildOptionIndex(nsIContent* aOptions,
+                                                    int32_t aStartIndex,
+                                                    int32_t aEndIndex) {
+  int32_t retval = -1;
+
+  for (int32_t i = aStartIndex; i < aEndIndex; ++i) {
+    retval = GetFirstOptionIndex(aOptions->GetChildAt_Deprecated(i));
+    if (retval != -1) {
+      break;
+    }
+  }
+
+  return retval;
+}
+
+nsISelectControlFrame* HTMLSelectElement::GetSelectFrame() {
+  nsIFormControlFrame* form_control_frame = GetFormControlFrame(false);
+
+  nsISelectControlFrame* select_frame = nullptr;
+
+  if (form_control_frame) {
+    select_frame = do_QueryFrame(form_control_frame);
+  }
+
+  return select_frame;
+}
+
+void HTMLSelectElement::Add(
+    const HTMLOptionElementOrHTMLOptGroupElement& aElement,
+    const Nullable<HTMLElementOrLong>& aBefore, ErrorResult& aRv) {
+  nsGenericHTMLElement& element =
+      aElement.IsHTMLOptionElement() ? static_cast<nsGenericHTMLElement&>(
+                                           aElement.GetAsHTMLOptionElement())
+                                     : static_cast<nsGenericHTMLElement&>(
+                                           aElement.GetAsHTMLOptGroupElement());
+
+  if (aBefore.IsNull()) {
+    Add(element, static_cast<nsGenericHTMLElement*>(nullptr), aRv);
+  } else if (aBefore.Value().IsHTMLElement()) {
+    Add(element, &aBefore.Value().GetAsHTMLElement(), aRv);
+  } else {
+    Add(element, aBefore.Value().GetAsLong(), aRv);
+  }
+}
+
+void HTMLSelectElement::Add(nsGenericHTMLElement& aElement,
+                            nsGenericHTMLElement* aBefore,
+                            ErrorResult& aError) {
+  if (!aBefore) {
+    Element::AppendChild(aElement, aError);
+    return;
+  }
+
+  // Just in case we're not the parent, get the parent of the reference
+  // element
+  nsCOMPtr<nsINode> parent = aBefore->Element::GetParentNode();
+  if (!parent || !parent->IsInclusiveDescendantOf(this)) {
+    // NOT_FOUND_ERR: Raised if before is not a descendant of the SELECT
+    // element.
+    aError.Throw(NS_ERROR_DOM_NOT_FOUND_ERR);
+    return;
+  }
+
+  // If the before parameter is not null, we are equivalent to the
+  // insertBefore method on the parent of before.
+  nsCOMPtr<nsINode> refNode = aBefore;
+  parent->InsertBefore(aElement, refNode, aError);
+}
+
+void HTMLSelectElement::Remove(int32_t aIndex) const {
+  if (aIndex < 0) {
+    return;
+  }
+
+  nsCOMPtr<nsINode> option = Item(static_cast<uint32_t>(aIndex));
+  if (!option) {
+    return;
+  }
+
+  option->Remove();
+}
+
+void HTMLSelectElement::GetType(nsAString& aType) {
+  if (HasAttr(nsGkAtoms::multiple)) {
+    aType.AssignLiteral("select-multiple");
+  } else {
+    aType.AssignLiteral("select-one");
+  }
+}
+
+void HTMLSelectElement::SetLength(uint32_t aLength, ErrorResult& aRv) {
+  constexpr uint32_t kMaxDynamicSelectLength = 100000;
+
+  uint32_t curlen = Length();
+
+  if (curlen > aLength) {  // Remove extra options
+    for (uint32_t i = curlen; i > aLength; --i) {
+      Remove(i - 1);
+    }
+  } else if (aLength > curlen) {
+    if (aLength > kMaxDynamicSelectLength) {
+      nsAutoString strOptionsLength;
+      strOptionsLength.AppendInt(aLength);
+
+      nsAutoString strLimit;
+      strLimit.AppendInt(kMaxDynamicSelectLength);
+
+      nsContentUtils::ReportToConsole(
+          nsIScriptError::warningFlag, "DOM"_ns, OwnerDoc(),
+          nsContentUtils::eDOM_PROPERTIES,
+          "SelectOptionsLengthAssignmentWarning", {strOptionsLength, strLimit});
+      return;
+    }
+
+    RefPtr<mozilla::dom::NodeInfo> nodeInfo;
+
+    nsContentUtils::QNameChanged(mNodeInfo, nsGkAtoms::option,
+                                 getter_AddRefs(nodeInfo));
+
+    nsCOMPtr<nsINode> node = NS_NewHTMLOptionElement(nodeInfo.forget());
+    for (uint32_t i = curlen; i < aLength; i++) {
+      nsINode::AppendChild(*node, aRv);
+      if (aRv.Failed()) {
+        return;
+      }
+
+      if (i + 1 < aLength) {
+        node = node->CloneNode(true, aRv);
+        if (aRv.Failed()) {
+          return;
+        }
+        MOZ_ASSERT(node);
+      }
+    }
+  }
+}
+
+/* static */
+bool HTMLSelectElement::MatchSelectedOptions(Element* aElement,
+                                             int32_t /* unused */,
+                                             nsAtom* /* unused */,
+                                             void* /* unused*/) {
+  HTMLOptionElement* option = HTMLOptionElement::FromNode(aElement);
+  return option && option->Selected();
+}
+
+nsIHTMLCollection* HTMLSelectElement::SelectedOptions() {
+  if (!mSelectedOptions) {
+    mSelectedOptions = new nsContentList(this, MatchSelectedOptions, nullptr,
+                                         nullptr, /* deep */ true);
+  }
+  return mSelectedOptions;
+}
+
+void HTMLSelectElement::SetSelectedIndexInternal(int32_t aIndex, bool aNotify) {
+  int32_t oldSelectedIndex = mSelectedIndex;
+  OptionFlags mask{OptionFlag::IsSelected, OptionFlag::ClearAll,
+                   OptionFlag::SetDisabled};
+  if (aNotify) {
+    mask += OptionFlag::Notify;
+  }
+
+  SetOptionsSelectedByIndex(aIndex, aIndex, mask);
+
+  nsISelectControlFrame* selectFrame = GetSelectFrame();
+  if (selectFrame) {
+    selectFrame->OnSetSelectedIndex(oldSelectedIndex, mSelectedIndex);
+  }
+
+  OnSelectionChanged();
+}
+
+bool HTMLSelectElement::IsOptionSelectedByIndex(int32_t aIndex) const {
+  HTMLOptionElement* option = Item(static_cast<uint32_t>(aIndex));
+  return option && option->Selected();
+}
+
+void HTMLSelectElement::OnOptionSelected(nsISelectControlFrame* aSelectFrame,
+                                         int32_t aIndex, bool aSelected,
+                                         bool aChangeOptionState,
+                                         bool aNotify) {
+  // Set the selected index
+  if (aSelected && (aIndex < mSelectedIndex || mSelectedIndex < 0)) {
+    mSelectedIndex = aIndex;
+    OnSelectionChanged();
+  } else if (!aSelected && aIndex == mSelectedIndex) {
+    FindSelectedIndex(aIndex + 1, aNotify);
+  }
+
+  if (aChangeOptionState) {
+    // Tell the option to get its bad self selected
+    RefPtr<HTMLOptionElement> option = Item(static_cast<uint32_t>(aIndex));
+    if (option) {
+      option->SetSelectedInternal(aSelected, aNotify);
+    }
+  }
+
+  // Let the frame know too
+  if (aSelectFrame) {
+    aSelectFrame->OnOptionSelected(aIndex, aSelected);
+  }
+
+  UpdateSelectedOptions();
+  UpdateValueMissingValidityState();
+  UpdateValidityElementStates(aNotify);
+}
+
+void HTMLSelectElement::FindSelectedIndex(int32_t aStartIndex, bool aNotify) {
+  mSelectedIndex = -1;
+  uint32_t len = Length();
+  for (int32_t i = aStartIndex; i < int32_t(len); i++) {
+    if (IsOptionSelectedByIndex(i)) {
+      mSelectedIndex = i;
+      break;
+    }
+  }
+  OnSelectionChanged();
+}
+
+// XXX Consider splitting this into two functions for ease of reading:
+// SelectOptionsByIndex(startIndex, endIndex, clearAll, checkDisabled)
+//   startIndex, endIndex - the range of options to turn on
+//                          (-1, -1) will clear all indices no matter what.
+//   clearAll - will clear all other options unless checkDisabled is on
+//              and all the options attempted to be set are disabled
+//              (note that if it is not multiple, and an option is selected,
+//              everything else will be cleared regardless).
+//   checkDisabled - if this is TRUE, and an option is disabled, it will not be
+//                   changed regardless of whether it is selected or not.
+//                   Generally the UI passes TRUE and JS passes FALSE.
+//                   (setDisabled currently is the opposite)
+// DeselectOptionsByIndex(startIndex, endIndex, checkDisabled)
+//   startIndex, endIndex - the range of options to turn on
+//                          (-1, -1) will clear all indices no matter what.
+//   checkDisabled - if this is TRUE, and an option is disabled, it will not be
+//                   changed regardless of whether it is selected or not.
+//                   Generally the UI passes TRUE and JS passes FALSE.
+//                   (setDisabled currently is the opposite)
+//
+// XXXbz the above comment is pretty confusing.  Maybe we should actually
+// document the args to this function too, in addition to documenting what
+// things might end up looking like?  In particular, pay attention to the
+// setDisabled vs checkDisabled business.
+bool HTMLSelectElement::SetOptionsSelectedByIndex(int32_t aStartIndex,
+                                                  int32_t aEndIndex,
+                                                  OptionFlags aOptionsMask) {
+#if 0
+  printf("SetOption(%d-%d, %c, ClearAll=%c)\n", aStartIndex, aEndIndex,
+                                      (aOptionsMask.contains(OptionFlag::IsSelected) ? 'Y' : 'N'),
+                                      (aOptionsMask.contains(OptionFlag::ClearAll) ? 'Y' : 'N'));
+#endif
+  // Don't bother if the select is disabled
+  if (!aOptionsMask.contains(OptionFlag::SetDisabled) && IsDisabled()) {
+    return false;
+  }
+
+  // Don't bother if there are no options
+  uint32_t numItems = Length();
+  if (numItems == 0) {
+    return false;
+  }
+
+  // First, find out whether multiple items can be selected
+  bool isMultiple = Multiple();
+
+  // These variables tell us whether any options were selected
+  // or deselected.
+  bool optionsSelected = false;
+  bool optionsDeselected = false;
+
+  nsISelectControlFrame* selectFrame = nullptr;
+  bool didGetFrame = false;
+  AutoWeakFrame weakSelectFrame;
+
+  if (aOptionsMask.contains(OptionFlag::IsSelected)) {
+    // Setting selectedIndex to an out-of-bounds index means -1. (HTML5)
+    if (aStartIndex < 0 || AssertedCast<uint32_t>(aStartIndex) >= numItems ||
+        aEndIndex < 0 || AssertedCast<uint32_t>(aEndIndex) >= numItems) {
+      aStartIndex = -1;
+      aEndIndex = -1;
+    }
+
+    // Only select the first value if it's not multiple
+    if (!isMultiple) {
+      aEndIndex = aStartIndex;
+    }
+
+    // This variable tells whether or not all of the options we attempted to
+    // select are disabled.  If ClearAll is passed in as true, and we do not
+    // select anything because the options are disabled, we will not clear the
+    // other options.  (This is to make the UI work the way one might expect.)
+    bool allDisabled = !aOptionsMask.contains(OptionFlag::SetDisabled);
+
+    //
+    // Save a little time when clearing other options
+    //
+    int32_t previousSelectedIndex = mSelectedIndex;
+
+    //
+    // Select the requested indices
+    //
+    // If index is -1, everything will be deselected (bug 28143)
+    if (aStartIndex != -1) {
+      MOZ_ASSERT(aStartIndex >= 0);
+      MOZ_ASSERT(aEndIndex >= 0);
+      // Loop through the options and select them (if they are not disabled and
+      // if they are not already selected).
+      for (uint32_t optIndex = AssertedCast<uint32_t>(aStartIndex);
+           optIndex <= AssertedCast<uint32_t>(aEndIndex); optIndex++) {
+        RefPtr<HTMLOptionElement> option = Item(optIndex);
+
+        // Ignore disabled options.
+        if (!aOptionsMask.contains(OptionFlag::SetDisabled)) {
+          if (option && IsOptionDisabled(option)) {
+            continue;
+          }
+          allDisabled = false;
+        }
+
+        // If the index is already selected, ignore it. On the other hand when
+        // the option has just been inserted we have to get in sync with it.
+        if (option && (aOptionsMask.contains(OptionFlag::InsertingOptions) ||
+                       !option->Selected())) {
+          // To notify the frame if anything gets changed. No need
+          // to flush here, if there's no frame yet we don't need to
+          // force it to be created just to notify it about a change
+          // in the select.
+          selectFrame = GetSelectFrame();
+          weakSelectFrame = do_QueryFrame(selectFrame);
+          didGetFrame = true;
+
+          OnOptionSelected(selectFrame, optIndex, true, !option->Selected(),
+                           aOptionsMask.contains(OptionFlag::Notify));
+          optionsSelected = true;
+        }
+      }
+    }
+
+    // Next remove all other options if single select or all is clear
+    // If index is -1, everything will be deselected (bug 28143)
+    if (((!isMultiple && optionsSelected) ||
+         (aOptionsMask.contains(OptionFlag::ClearAll) && !allDisabled) ||
+         aStartIndex == -1) &&
+        previousSelectedIndex != -1) {
+      for (uint32_t optIndex = AssertedCast<uint32_t>(previousSelectedIndex);
+           optIndex < numItems; optIndex++) {
+        if (static_cast<int32_t>(optIndex) < aStartIndex ||
+            static_cast<int32_t>(optIndex) > aEndIndex) {
+          HTMLOptionElement* option = Item(optIndex);
+          // If the index is already deselected, ignore it.
+          if (option && option->Selected()) {
+            if (!didGetFrame || (selectFrame && !weakSelectFrame.IsAlive())) {
+              // To notify the frame if anything gets changed, don't
+              // flush, if the frame doesn't exist we don't need to
+              // create it just to tell it about this change.
+              selectFrame = GetSelectFrame();
+              weakSelectFrame = do_QueryFrame(selectFrame);
+
+              didGetFrame = true;
+            }
+
+            OnOptionSelected(selectFrame, optIndex, false, true,
+                             aOptionsMask.contains(OptionFlag::Notify));
+            optionsDeselected = true;
+
+            // Only need to deselect one option if not multiple
+            if (!isMultiple) {
+              break;
+            }
+          }
+        }
+      }
+    }
+  } else {
+    // If we're deselecting, loop through all selected items and deselect
+    // any that are in the specified range.
+    for (int32_t optIndex = aStartIndex; optIndex <= aEndIndex; optIndex++) {
+      HTMLOptionElement* option = Item(optIndex);
+      if (!aOptionsMask.contains(OptionFlag::SetDisabled) &&
+          IsOptionDisabled(option)) {
+        continue;
+      }
+
+      // If the index is already selected, ignore it.
+      if (option && option->Selected()) {
+        if (!didGetFrame || (selectFrame && !weakSelectFrame.IsAlive())) {
+          // To notify the frame if anything gets changed, don't
+          // flush, if the frame doesn't exist we don't need to
+          // create it just to tell it about this change.
+          selectFrame = GetSelectFrame();
+          weakSelectFrame = do_QueryFrame(selectFrame);
+
+          didGetFrame = true;
+        }
+
+        OnOptionSelected(selectFrame, optIndex, false, true,
+                         aOptionsMask.contains(OptionFlag::Notify));
+        optionsDeselected = true;
+      }
+    }
+  }
+
+  // Make sure something is selected unless we were set to -1 (none)
+  if (optionsDeselected && aStartIndex != -1 &&
+      !aOptionsMask.contains(OptionFlag::NoReselect)) {
+    optionsSelected =
+        CheckSelectSomething(aOptionsMask.contains(OptionFlag::Notify)) ||
+        optionsSelected;
+  }
+
+  // Let the caller know whether anything was changed
+  return optionsSelected || optionsDeselected;
+}
+
+NS_IMETHODIMP
+HTMLSelectElement::IsOptionDisabled(int32_t aIndex, bool* aIsDisabled) {
+  *aIsDisabled = false;
+  RefPtr<HTMLOptionElement> option = Item(aIndex);
+  NS_ENSURE_TRUE(option, NS_ERROR_FAILURE);
+
+  *aIsDisabled = IsOptionDisabled(option);
+  return NS_OK;
+}
+
+bool HTMLSelectElement::IsOptionDisabled(HTMLOptionElement* aOption) const {
+  MOZ_ASSERT(aOption);
+  if (aOption->Disabled()) {
+    return true;
+  }
+
+  // Check for disabled optgroups
+  // If there are no artifacts, there are no optgroups
+  if (mNonOptionChildren) {
+    for (nsCOMPtr<Element> node =
+             static_cast<nsINode*>(aOption)->GetParentElement();
+         node; node = node->GetParentElement()) {
+      // If we reached the select element, we're done
+      if (node->IsHTMLElement(nsGkAtoms::select)) {
+        return false;
+      }
+
+      RefPtr<HTMLOptGroupElement> optGroupElement =
+          HTMLOptGroupElement::FromNode(node);
+
+      if (!optGroupElement) {
+        // If you put something else between you and the optgroup, you're a
+        // moron and you deserve not to have optgroup disabling work.
+        return false;
+      }
+
+      if (optGroupElement->Disabled()) {
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+void HTMLSelectElement::GetValue(DOMString& aValue) const {
+  int32_t selectedIndex = SelectedIndex();
+  if (selectedIndex < 0) {
+    return;
+  }
+
+  RefPtr<HTMLOptionElement> option = Item(static_cast<uint32_t>(selectedIndex));
+
+  if (!option) {
+    return;
+  }
+
+  option->GetValue(aValue);
+}
+
+void HTMLSelectElement::SetValue(const nsAString& aValue) {
+  uint32_t length = Length();
+
+  for (uint32_t i = 0; i < length; i++) {
+    RefPtr<HTMLOptionElement> option = Item(i);
+    if (!option) {
+      continue;
+    }
+
+    nsAutoString optionVal;
+    option->GetValue(optionVal);
+    if (optionVal.Equals(aValue)) {
+      SetSelectedIndexInternal(int32_t(i), true);
+      return;
+    }
+  }
+  // No matching option was found.
+  SetSelectedIndexInternal(-1, true);
+}
+
+int32_t HTMLSelectElement::TabIndexDefault() { return 0; }
+
+bool HTMLSelectElement::IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
+                                        int32_t* aTabIndex) {
+  if (nsGenericHTMLFormControlElementWithState::IsHTMLFocusable(
+          aWithMouse, aIsFocusable, aTabIndex)) {
+    return true;
+  }
+
+  *aIsFocusable = !IsDisabled();
+
+  return false;
+}
+
+bool HTMLSelectElement::CheckSelectSomething(bool aNotify) {
+  if (mIsDoneAddingChildren) {
+    if (mSelectedIndex < 0 && IsCombobox()) {
+      return SelectSomething(aNotify);
+    }
+  }
+  return false;
+}
+
+bool HTMLSelectElement::SelectSomething(bool aNotify) {
+  // If we're not done building the select, don't play with this yet.
+  if (!mIsDoneAddingChildren) {
+    return false;
+  }
+
+  uint32_t count = Length();
+  for (uint32_t i = 0; i < count; i++) {
+    bool disabled;
+    nsresult rv = IsOptionDisabled(i, &disabled);
+
+    if (NS_FAILED(rv) || !disabled) {
+      SetSelectedIndexInternal(i, aNotify);
+
+      UpdateValueMissingValidityState();
+      UpdateValidityElementStates(aNotify);
+
+      return true;
+    }
+  }
+
+  return false;
+}
+
+nsresult HTMLSelectElement::BindToTree(BindContext& aContext,
+                                       nsINode& aParent) {
+  nsresult rv =
+      nsGenericHTMLFormControlElementWithState::BindToTree(aContext, aParent);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // If there is a disabled fieldset in the parent chain, the element is now
+  // barred from constraint validation.
+  // XXXbz is this still needed now that fieldset changes always call
+  // FieldSetDisabledChanged?
+  UpdateBarredFromConstraintValidation();
+
+  // And now make sure our state is up to date
+  UpdateValidityElementStates(false);
+
+  return rv;
+}
+
+void HTMLSelectElement::UnbindFromTree(bool aNullParent) {
+  nsGenericHTMLFormControlElementWithState::UnbindFromTree(aNullParent);
+
+  // We might be no longer disabled because our parent chain changed.
+  // XXXbz is this still needed now that fieldset changes always call
+  // FieldSetDisabledChanged?
+  UpdateBarredFromConstraintValidation();
+
+  // And now make sure our state is up to date
+  UpdateValidityElementStates(false);
+}
+
+void HTMLSelectElement::BeforeSetAttr(int32_t aNameSpaceID, nsAtom* aName,
+                                      const nsAttrValue* aValue, bool aNotify) {
+  if (aNameSpaceID == kNameSpaceID_None) {
+    if (aName == nsGkAtoms::disabled) {
+      if (aNotify) {
+        mDisabledChanged = true;
+      }
+    } else if (aName == nsGkAtoms::multiple) {
+      if (!aValue && aNotify && mSelectedIndex >= 0) {
+        // We're changing from being a multi-select to a single-select.
+        // Make sure we only have one option selected before we do that.
+        // Note that this needs to come before we really unset the attr,
+        // since SetOptionsSelectedByIndex does some bail-out type
+        // optimization for cases when the select is not multiple that
+        // would lead to only a single option getting deselected.
+        SetSelectedIndexInternal(mSelectedIndex, aNotify);
+      }
+    }
+  }
+
+  return nsGenericHTMLFormControlElementWithState::BeforeSetAttr(
+      aNameSpaceID, aName, aValue, aNotify);
+}
+
+void HTMLSelectElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
+                                     const nsAttrValue* aValue,
+                                     const nsAttrValue* aOldValue,
+                                     nsIPrincipal* aSubjectPrincipal,
+                                     bool aNotify) {
+  if (aNameSpaceID == kNameSpaceID_None) {
+    if (aName == nsGkAtoms::disabled) {
+      // This *has* to be called *before* validity state check because
+      // UpdateBarredFromConstraintValidation and
+      // UpdateValueMissingValidityState depend on our disabled state.
+      UpdateDisabledState(aNotify);
+
+      UpdateValueMissingValidityState();
+      UpdateBarredFromConstraintValidation();
+      UpdateValidityElementStates(aNotify);
+    } else if (aName == nsGkAtoms::required) {
+      // This *has* to be called *before* UpdateValueMissingValidityState
+      // because UpdateValueMissingValidityState depends on our required
+      // state.
+      UpdateRequiredState(!!aValue, aNotify);
+      UpdateValueMissingValidityState();
+      UpdateValidityElementStates(aNotify);
+    } else if (aName == nsGkAtoms::autocomplete) {
+      // Clear the cached @autocomplete attribute and autocompleteInfo state.
+      mAutocompleteAttrState = nsContentUtils::eAutocompleteAttrState_Unknown;
+      mAutocompleteInfoState = nsContentUtils::eAutocompleteAttrState_Unknown;
+    } else if (aName == nsGkAtoms::multiple) {
+      if (!aValue && aNotify) {
+        // We might have become a combobox; make sure _something_ gets
+        // selected in that case
+        CheckSelectSomething(aNotify);
+      }
+    }
+  }
+
+  return nsGenericHTMLFormControlElementWithState::AfterSetAttr(
+      aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
+}
+
+void HTMLSelectElement::DoneAddingChildren(bool aHaveNotified) {
+  mIsDoneAddingChildren = true;
+
+  nsISelectControlFrame* selectFrame = GetSelectFrame();
+
+  // If we foolishly tried to restore before we were done adding
+  // content, restore the rest of the options proper-like
+  if (mRestoreState) {
+    RestoreStateTo(*mRestoreState);
+    mRestoreState = nullptr;
+  }
+
+  // Notify the frame
+  if (selectFrame) {
+    selectFrame->DoneAddingChildren(true);
+  }
+
+  if (!mInhibitStateRestoration) {
+    GenerateStateKey();
+    RestoreFormControlState();
+  }
+
+  // Now that we're done, select something (if it's a single select something
+  // must be selected)
+  if (!CheckSelectSomething(false)) {
+    // If an option has @selected set, it will be selected during parsing but
+    // with an empty value. We have to make sure the select element updates it's
+    // validity state to take this into account.
+    UpdateValueMissingValidityState();
+
+    // And now make sure we update our content state too
+    UpdateValidityElementStates(aHaveNotified);
+  }
+
+  mDefaultSelectionSet = true;
+}
+
+bool HTMLSelectElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+                                       const nsAString& aValue,
+                                       nsIPrincipal* aMaybeScriptedPrincipal,
+                                       nsAttrValue& aResult) {
+  if (kNameSpaceID_None == aNamespaceID) {
+    if (aAttribute == nsGkAtoms::size) {
+      return aResult.ParsePositiveIntValue(aValue);
+    }
+    if (aAttribute == nsGkAtoms::autocomplete) {
+      aResult.ParseAtomArray(aValue);
+      return true;
+    }
+  }
+  return nsGenericHTMLFormControlElementWithState::ParseAttribute(
+      aNamespaceID, aAttribute, aValue, aMaybeScriptedPrincipal, aResult);
+}
+
+void HTMLSelectElement::MapAttributesIntoRule(
+    MappedDeclarationsBuilder& aBuilder) {
+  nsGenericHTMLFormControlElementWithState::MapImageAlignAttributeInto(
+      aBuilder);
+  nsGenericHTMLFormControlElementWithState::MapCommonAttributesInto(aBuilder);
+}
+
+nsChangeHint HTMLSelectElement::GetAttributeChangeHint(const nsAtom* aAttribute,
+                                                       int32_t aModType) const {
+  nsChangeHint retval =
+      nsGenericHTMLFormControlElementWithState::GetAttributeChangeHint(
+          aAttribute, aModType);
+  if (aAttribute == nsGkAtoms::multiple || aAttribute == nsGkAtoms::size) {
+    retval |= nsChangeHint_ReconstructFrame;
+  }
+  return retval;
+}
+
+NS_IMETHODIMP_(bool)
+HTMLSelectElement::IsAttributeMapped(const nsAtom* aAttribute) const {
+  static const MappedAttributeEntry* const map[] = {sCommonAttributeMap,
+                                                    sImageAlignAttributeMap};
+
+  return FindAttributeDependence(aAttribute, map);
+}
+
+nsMapRuleToAttributesFunc HTMLSelectElement::GetAttributeMappingFunction()
+    const {
+  return &MapAttributesIntoRule;
+}
+
+bool HTMLSelectElement::IsDisabledForEvents(WidgetEvent* aEvent) {
+  nsIFormControlFrame* formControlFrame = GetFormControlFrame(false);
+  nsIFrame* formFrame = nullptr;
+  if (formControlFrame) {
+    formFrame = do_QueryFrame(formControlFrame);
+  }
+  return IsElementDisabledForEvents(aEvent, formFrame);
+}
+
+void HTMLSelectElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
+  aVisitor.mCanHandle = false;
+  if (IsDisabledForEvents(aVisitor.mEvent)) {
+    return;
+  }
+
+  nsGenericHTMLFormControlElementWithState::GetEventTargetParent(aVisitor);
+}
+
+void HTMLSelectElement::UpdateValidityElementStates(bool aNotify) {
+  AutoStateChangeNotifier notifier(*this, aNotify);
+  RemoveStatesSilently(ElementState::VALIDITY_STATES);
+  if (!IsCandidateForConstraintValidation()) {
+    return;
+  }
+
+  ElementState state;
+  if (IsValid()) {
+    state |= ElementState::VALID;
+    if (mUserInteracted) {
+      state |= ElementState::USER_VALID;
+    }
+  } else {
+    state |= ElementState::INVALID;
+    if (mUserInteracted) {
+      state |= ElementState::USER_INVALID;
+    }
+  }
+
+  AddStatesSilently(state);
+}
+
+void HTMLSelectElement::SaveState() {
+  PresState* presState = GetPrimaryPresState();
+  if (!presState) {
+    return;
+  }
+
+  SelectContentData state;
+
+  uint32_t len = Length();
+
+  for (uint32_t optIndex = 0; optIndex < len; optIndex++) {
+    HTMLOptionElement* option = Item(optIndex);
+    if (option && option->Selected()) {
+      nsAutoString value;
+      option->GetValue(value);
+      if (value.IsEmpty()) {
+        state.indices().AppendElement(optIndex);
+      } else {
+        state.values().AppendElement(std::move(value));
+      }
+    }
+  }
+
+  presState->contentData() = std::move(state);
+
+  if (mDisabledChanged) {
+    // We do not want to save the real disabled state but the disabled
+    // attribute.
+    presState->disabled() = HasAttr(nsGkAtoms::disabled);
+    presState->disabledSet() = true;
+  }
+}
+
+bool HTMLSelectElement::RestoreState(PresState* aState) {
+  // Get the presentation state object to retrieve our stuff out of.
+  const PresContentData& state = aState->contentData();
+  if (state.type() == PresContentData::TSelectContentData) {
+    RestoreStateTo(state.get_SelectContentData());
+
+    // Don't flush, if the frame doesn't exist yet it doesn't care if
+    // we're reset or not.
+    DispatchContentReset();
+  }
+
+  if (aState->disabledSet() && !aState->disabled()) {
+    SetDisabled(false, IgnoreErrors());
+  }
+
+  return false;
+}
+
+void HTMLSelectElement::RestoreStateTo(const SelectContentData& aNewSelected) {
+  if (!mIsDoneAddingChildren) {
+    // Make a copy of the state for us to restore from in the future.
+    mRestoreState = MakeUnique<SelectContentData>(aNewSelected);
+    return;
+  }
+
+  uint32_t len = Length();
+  OptionFlags mask{OptionFlag::IsSelected, OptionFlag::ClearAll,
+                   OptionFlag::SetDisabled, OptionFlag::Notify};
+
+  // First clear all
+  SetOptionsSelectedByIndex(-1, -1, mask);
+
+  // Select by index.
+  for (uint32_t idx : aNewSelected.indices()) {
+    if (idx < len) {
+      SetOptionsSelectedByIndex(idx, idx,
+                                {OptionFlag::IsSelected,
+                                 OptionFlag::SetDisabled, OptionFlag::Notify});
+    }
+  }
+
+  // Select by value.
+  for (uint32_t i = 0; i < len; ++i) {
+    HTMLOptionElement* option = Item(i);
+    if (option) {
+      nsAutoString value;
+      option->GetValue(value);
+      if (aNewSelected.values().Contains(value)) {
+        SetOptionsSelectedByIndex(
+            i, i,
+            {OptionFlag::IsSelected, OptionFlag::SetDisabled,
+             OptionFlag::Notify});
+      }
+    }
+  }
+}
+
+// nsIFormControl
+
+NS_IMETHODIMP
+HTMLSelectElement::Reset() {
+  uint32_t numSelected = 0;
+
+  //
+  // Cycle through the options array and reset the options
+  //
+  uint32_t numOptions = Length();
+
+  for (uint32_t i = 0; i < numOptions; i++) {
+    RefPtr<HTMLOptionElement> option = Item(i);
+    if (option) {
+      //
+      // Reset the option to its default value
+      //
+
+      OptionFlags mask = {OptionFlag::SetDisabled, OptionFlag::Notify,
+                          OptionFlag::NoReselect};
+      if (option->DefaultSelected()) {
+        mask += OptionFlag::IsSelected;
+        numSelected++;
+      }
+
+      SetOptionsSelectedByIndex(i, i, mask);
+      option->SetSelectedChanged(false);
+    }
+  }
+
+  //
+  // If nothing was selected and it's not multiple, select something
+  //
+  if (numSelected == 0 && IsCombobox()) {
+    SelectSomething(true);
+  }
+
+  OnSelectionChanged();
+  SetUserInteracted(false);
+
+  // Let the frame know we were reset
+  //
+  // Don't flush, if there's no frame yet it won't care about us being
+  // reset even if we forced it to be created now.
+  //
+  DispatchContentReset();
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+HTMLSelectElement::SubmitNamesValues(FormData* aFormData) {
+  //
+  // Get the name (if no name, no submit)
+  //
+  nsAutoString name;
+  GetAttr(nsGkAtoms::name, name);
+  if (name.IsEmpty()) {
+    return NS_OK;
+  }
+
+  //
+  // Submit
+  //
+  uint32_t len = Length();
+
+  for (uint32_t optIndex = 0; optIndex < len; optIndex++) {
+    HTMLOptionElement* option = Item(optIndex);
+
+    // Don't send disabled options
+    if (!option || IsOptionDisabled(option)) {
+      continue;
+    }
+
+    if (!option->Selected()) {
+      continue;
+    }
+
+    nsString value;
+    option->GetValue(value);
+
+    aFormData->AddNameValuePair(name, value);
+  }
+
+  return NS_OK;
+}
+
+void HTMLSelectElement::DispatchContentReset() {
+  if (nsIFormControlFrame* formControlFrame = GetFormControlFrame(false)) {
+    if (nsListControlFrame* listFrame = do_QueryFrame(formControlFrame)) {
+      listFrame->OnContentReset();
+    }
+  }
+}
+
+static void AddOptions(nsIContent* aRoot, HTMLOptionsCollection* aArray) {
+  for (nsIContent* child = aRoot->GetFirstChild(); child;
+       child = child->GetNextSibling()) {
+    HTMLOptionElement* opt = HTMLOptionElement::FromNode(child);
+    if (opt) {
+      aArray->AppendOption(opt);
+    } else if (child->IsHTMLElement(nsGkAtoms::optgroup)) {
+      for (nsIContent* grandchild = child->GetFirstChild(); grandchild;
+           grandchild = grandchild->GetNextSibling()) {
+        opt = HTMLOptionElement::FromNode(grandchild);
+        if (opt) {
+          aArray->AppendOption(opt);
+        }
+      }
+    }
+  }
+}
+
+void HTMLSelectElement::RebuildOptionsArray(bool aNotify) {
+  mOptions->Clear();
+  AddOptions(this, mOptions);
+  FindSelectedIndex(0, aNotify);
+}
+
+bool HTMLSelectElement::IsValueMissing() const {
+  if (!Required()) {
+    return false;
+  }
+
+  uint32_t length = Length();
+
+  for (uint32_t i = 0; i < length; ++i) {
+    RefPtr<HTMLOptionElement> option = Item(i);
+    // Check for a placeholder label option, don't count it as a valid value.
+    if (i == 0 && !Multiple() && Size() <= 1 && option->GetParent() == this) {
+      nsAutoString value;
+      option->GetValue(value);
+      if (value.IsEmpty()) {
+        continue;
+      }
+    }
+
+    if (!option->Selected()) {
+      continue;
+    }
+
+    return false;
+  }
+
+  return true;
+}
+
+void HTMLSelectElement::UpdateValueMissingValidityState() {
+  SetValidityState(VALIDITY_STATE_VALUE_MISSING, IsValueMissing());
+}
+
+nsresult HTMLSelectElement::GetValidationMessage(nsAString& aValidationMessage,
+                                                 ValidityStateType aType) {
+  switch (aType) {
+    case VALIDITY_STATE_VALUE_MISSING: {
+      nsAutoString message;
+      nsresult rv = nsContentUtils::GetMaybeLocalizedString(
+          nsContentUtils::eDOM_PROPERTIES, "FormValidationSelectMissing",
+          OwnerDoc(), message);
+      aValidationMessage = message;
+      return rv;
+    }
+    default: {
+      return ConstraintValidation::GetValidationMessage(aValidationMessage,
+                                                        aType);
+    }
+  }
+}
+
+#ifdef DEBUG
+
+void HTMLSelectElement::VerifyOptionsArray() {
+  int32_t index = 0;
+  for (nsIContent* child = nsINode::GetFirstChild(); child;
+       child = child->GetNextSibling()) {
+    HTMLOptionElement* opt = HTMLOptionElement::FromNode(child);
+    if (opt) {
+      NS_ASSERTION(opt == mOptions->ItemAsOption(index++),
+                   "Options collection broken");
+    } else if (child->IsHTMLElement(nsGkAtoms::optgroup)) {
+      for (nsIContent* grandchild = child->GetFirstChild(); grandchild;
+           grandchild = grandchild->GetNextSibling()) {
+        opt = HTMLOptionElement::FromNode(grandchild);
+        if (opt) {
+          NS_ASSERTION(opt == mOptions->ItemAsOption(index++),
+                       "Options collection broken");
+        }
+      }
+    }
+  }
+}
+
+#endif
+
+void HTMLSelectElement::UpdateBarredFromConstraintValidation() {
+  SetBarredFromConstraintValidation(
+      HasFlag(ELEMENT_IS_DATALIST_OR_HAS_DATALIST_ANCESTOR) || IsDisabled());
+}
+
+void HTMLSelectElement::FieldSetDisabledChanged(bool aNotify) {
+  // This *has* to be called before UpdateBarredFromConstraintValidation and
+  // UpdateValueMissingValidityState because these two functions depend on our
+  // disabled state.
+  nsGenericHTMLFormControlElementWithState::FieldSetDisabledChanged(aNotify);
+
+  UpdateValueMissingValidityState();
+  UpdateBarredFromConstraintValidation();
+  UpdateValidityElementStates(aNotify);
+}
+
+void HTMLSelectElement::OnSelectionChanged() {
+  if (!mDefaultSelectionSet) {
+    return;
+  }
+  UpdateSelectedOptions();
+}
+
+void HTMLSelectElement::UpdateSelectedOptions() {
+  if (mSelectedOptions) {
+    mSelectedOptions->SetDirty();
+  }
+}
+
+void HTMLSelectElement::SetUserInteracted(bool aInteracted) {
+  if (mUserInteracted == aInteracted) {
+    return;
+  }
+  mUserInteracted = aInteracted;
+  UpdateValidityElementStates(true);
+}
+
+void HTMLSelectElement::SetPreviewValue(const nsAString& aValue) {
+  mPreviewValue = aValue;
+  nsContentUtils::RemoveNewlines(mPreviewValue);
+  nsIFormControlFrame* formControlFrame = GetFormControlFrame(false);
+  nsComboboxControlFrame* comboFrame = do_QueryFrame(formControlFrame);
+  if (comboFrame) {
+    comboFrame->RedisplaySelectedText();
+  }
+}
+
+void HTMLSelectElement::UserFinishedInteracting(bool aChanged) {
+  SetUserInteracted(true);
+  if (!aChanged) {
+    return;
+  }
+
+  // Dispatch the input event.
+  DebugOnly<nsresult> rvIgnored = nsContentUtils::DispatchInputEvent(this);
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                       "Failed to dispatch input event");
+
+  // Dispatch the change event.
+  nsContentUtils::DispatchTrustedEvent(OwnerDoc(), this, u"change"_ns,
+                                       CanBubble::eYes, Cancelable::eNo);
+}
+
+JSObject* HTMLSelectElement::WrapNode(JSContext* aCx,
+                                      JS::Handle<JSObject*> aGivenProto) {
+  return HTMLSelectElement_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+}  // namespace mozilla::dom