Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 481 insertions, 0 deletions

diff --git a/layout/generic/ViewportFrame.cpp b/layout/generic/ViewportFrame.cpp
new file mode 100644
index 0000000000..1837441e86
--- /dev/null
+++ b/layout/generic/ViewportFrame.cpp
@@ -0,0 +1,481 @@
+/* -*- 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/. */
+
+/*
+ * rendering object that is the root of the frame tree, which contains
+ * the document's scrollbars and contains fixed-positioned elements
+ */
+
+#include "mozilla/ViewportFrame.h"
+
+#include "mozilla/ComputedStyleInlines.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/ProfilerLabels.h"
+#include "mozilla/RestyleManager.h"
+#include "nsGkAtoms.h"
+#include "nsIScrollableFrame.h"
+#include "nsAbsoluteContainingBlock.h"
+#include "nsCanvasFrame.h"
+#include "nsLayoutUtils.h"
+#include "nsSubDocumentFrame.h"
+#include "nsIMozBrowserFrame.h"
+#include "nsPlaceholderFrame.h"
+#include "MobileViewportManager.h"
+
+using namespace mozilla;
+typedef nsAbsoluteContainingBlock::AbsPosReflowFlags AbsPosReflowFlags;
+
+ViewportFrame* NS_NewViewportFrame(PresShell* aPresShell,
+                                   ComputedStyle* aStyle) {
+  return new (aPresShell) ViewportFrame(aStyle, aPresShell->GetPresContext());
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(ViewportFrame)
+NS_QUERYFRAME_HEAD(ViewportFrame)
+  NS_QUERYFRAME_ENTRY(ViewportFrame)
+NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
+
+void ViewportFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
+                         nsIFrame* aPrevInFlow) {
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+  // No need to call CreateView() here - the frame ctor will call SetView()
+  // with the ViewManager's root view, so we'll assign it in SetViewInternal().
+
+  nsIFrame* parent = nsLayoutUtils::GetCrossDocParentFrameInProcess(this);
+  if (parent) {
+    nsFrameState state = parent->GetStateBits();
+
+    AddStateBits(state & (NS_FRAME_IN_POPUP));
+  }
+}
+
+void ViewportFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
+                                     const nsDisplayListSet& aLists) {
+  AUTO_PROFILER_LABEL("ViewportFrame::BuildDisplayList",
+                      GRAPHICS_DisplayListBuilding);
+
+  nsIFrame* kid = mFrames.FirstChild();
+  if (!kid) {
+    return;
+  }
+
+  nsDisplayListCollection set(aBuilder);
+  BuildDisplayListForChild(aBuilder, kid, set);
+
+  // If we have a scrollframe then it takes care of creating the display list
+  // for the top layer, but otherwise we need to do it here.
+  if (!kid->IsScrollFrame()) {
+    bool isOpaque = false;
+    if (auto* list = BuildDisplayListForTopLayer(aBuilder, &isOpaque)) {
+      if (isOpaque) {
+        set.DeleteAll(aBuilder);
+      }
+      set.PositionedDescendants()->AppendToTop(list);
+    }
+  }
+
+  set.MoveTo(aLists);
+}
+
+#ifdef DEBUG
+/**
+ * Returns whether we are going to put an element in the top layer for
+ * fullscreen. This function should matches the CSS rule in ua.css.
+ */
+static bool ShouldInTopLayerForFullscreen(dom::Element* aElement) {
+  return !!aElement->GetParent();
+}
+#endif  // DEBUG
+
+static void BuildDisplayListForTopLayerFrame(nsDisplayListBuilder* aBuilder,
+                                             nsIFrame* aFrame,
+                                             nsDisplayList* aList) {
+  nsRect visible;
+  nsRect dirty;
+  DisplayListClipState::AutoSaveRestore clipState(aBuilder);
+  nsDisplayListBuilder::AutoCurrentActiveScrolledRootSetter asrSetter(aBuilder);
+  nsDisplayListBuilder::OutOfFlowDisplayData* savedOutOfFlowData =
+      nsDisplayListBuilder::GetOutOfFlowData(aFrame);
+  if (savedOutOfFlowData) {
+    visible =
+        savedOutOfFlowData->GetVisibleRectForFrame(aBuilder, aFrame, &dirty);
+    // This function is called after we've finished building display items for
+    // the root scroll frame. That means that the content clip from the root
+    // scroll frame is no longer on aBuilder. However, we need to make sure
+    // that the display items we build in this function have finite clipped
+    // bounds with respect to the root ASR, so we restore the *combined clip*
+    // that we saved earlier. The combined clip will include the clip from the
+    // root scroll frame.
+    clipState.SetClipChainForContainingBlockDescendants(
+        savedOutOfFlowData->mCombinedClipChain);
+    asrSetter.SetCurrentActiveScrolledRoot(
+        savedOutOfFlowData->mContainingBlockActiveScrolledRoot);
+    asrSetter.SetCurrentScrollParentId(savedOutOfFlowData->mScrollParentId);
+  }
+  nsDisplayListBuilder::AutoBuildingDisplayList buildingForChild(
+      aBuilder, aFrame, visible, dirty);
+
+  nsDisplayList list(aBuilder);
+  aFrame->BuildDisplayListForStackingContext(aBuilder, &list);
+  aList->AppendToTop(&list);
+}
+
+static bool BackdropListIsOpaque(ViewportFrame* aFrame,
+                                 nsDisplayListBuilder* aBuilder,
+                                 nsDisplayList* aList) {
+  // The common case for ::backdrop elements on the top layer is a single
+  // fixed position container, holding an opaque background color covering
+  // the whole viewport.
+  if (aList->Length() != 1 ||
+      aList->GetTop()->GetType() != DisplayItemType::TYPE_FIXED_POSITION) {
+    return false;
+  }
+
+  // Make sure the fixed position container isn't clipped or scrollable.
+  nsDisplayFixedPosition* fixed =
+      static_cast<nsDisplayFixedPosition*>(aList->GetTop());
+  if (fixed->GetActiveScrolledRoot() || fixed->GetClipChain()) {
+    return false;
+  }
+
+  nsDisplayList* children = fixed->GetChildren();
+  if (!children->GetTop() ||
+      children->GetTop()->GetType() != DisplayItemType::TYPE_BACKGROUND_COLOR) {
+    return false;
+  }
+
+  nsDisplayBackgroundColor* child =
+      static_cast<nsDisplayBackgroundColor*>(children->GetTop());
+  if (child->GetActiveScrolledRoot() || child->GetClipChain()) {
+    return false;
+  }
+
+  // Check that the background color is both opaque, and covering the
+  // whole viewport.
+  bool dummy;
+  nsRegion opaque = child->GetOpaqueRegion(aBuilder, &dummy);
+  return opaque.Contains(aFrame->GetRect());
+}
+
+nsDisplayWrapList* ViewportFrame::BuildDisplayListForTopLayer(
+    nsDisplayListBuilder* aBuilder, bool* aIsOpaque) {
+  nsDisplayList topLayerList(aBuilder);
+
+  nsTArray<dom::Element*> topLayer = PresContext()->Document()->GetTopLayer();
+  for (dom::Element* elem : topLayer) {
+    nsIFrame* frame = elem->GetPrimaryFrame();
+    if (!frame) {
+      continue;
+    }
+
+    if (frame->IsHiddenByContentVisibilityOnAnyAncestor(
+            nsIFrame::IncludeContentVisibility::Hidden)) {
+      continue;
+    }
+
+    // There are two cases where an element in fullscreen is not in
+    // the top layer:
+    // 1. When building display list for purpose other than painting,
+    //    it is possible that there is inconsistency between the style
+    //    info and the content tree.
+    // 2. This is an element which we are not going to put in the top
+    //    layer for fullscreen. See ShouldInTopLayerForFullscreen().
+    // In both cases, we want to skip the frame here and paint it in
+    // the normal path.
+    if (frame->StyleDisplay()->mTopLayer == StyleTopLayer::None) {
+      MOZ_ASSERT(!aBuilder->IsForPainting() ||
+                 !ShouldInTopLayerForFullscreen(elem));
+      continue;
+    }
+    MOZ_ASSERT(ShouldInTopLayerForFullscreen(elem));
+    // Inner SVG, MathML elements, as well as children of some XUL
+    // elements are not allowed to be out-of-flow. They should not
+    // be handled as top layer element here.
+    if (!frame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW)) {
+      MOZ_ASSERT(!elem->GetParent()->IsHTMLElement(),
+                 "HTML element should always be out-of-flow if in the top "
+                 "layer");
+      continue;
+    }
+    if (nsIFrame* backdropPh =
+            frame->GetChildList(FrameChildListID::Backdrop).FirstChild()) {
+      MOZ_ASSERT(!backdropPh->GetNextSibling(), "more than one ::backdrop?");
+      MOZ_ASSERT(backdropPh->HasAnyStateBits(NS_FRAME_FIRST_REFLOW),
+                 "did you intend to reflow ::backdrop placeholders?");
+      nsIFrame* backdropFrame =
+          nsPlaceholderFrame::GetRealFrameForPlaceholder(backdropPh);
+      BuildDisplayListForTopLayerFrame(aBuilder, backdropFrame, &topLayerList);
+
+      if (aIsOpaque) {
+        *aIsOpaque = BackdropListIsOpaque(this, aBuilder, &topLayerList);
+      }
+    }
+    BuildDisplayListForTopLayerFrame(aBuilder, frame, &topLayerList);
+  }
+
+  if (nsCanvasFrame* canvasFrame = PresShell()->GetCanvasFrame()) {
+    if (dom::Element* container = canvasFrame->GetCustomContentContainer()) {
+      if (nsIFrame* frame = container->GetPrimaryFrame()) {
+        MOZ_ASSERT(frame->StyleDisplay()->mTopLayer != StyleTopLayer::None,
+                   "ua.css should ensure this");
+        MOZ_ASSERT(frame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW));
+        BuildDisplayListForTopLayerFrame(aBuilder, frame, &topLayerList);
+      }
+    }
+  }
+  if (topLayerList.IsEmpty()) {
+    return nullptr;
+  }
+  nsPoint offset = aBuilder->GetCurrentFrame()->GetOffsetTo(this);
+  nsDisplayListBuilder::AutoBuildingDisplayList buildingDisplayList(
+      aBuilder, this, aBuilder->GetVisibleRect() + offset,
+      aBuilder->GetDirtyRect() + offset);
+  // Wrap the whole top layer in a single item with maximum z-index,
+  // and append it at the very end, so that it stays at the topmost.
+  nsDisplayWrapList* wrapList = MakeDisplayItemWithIndex<nsDisplayWrapper>(
+      aBuilder, this, 2, &topLayerList, aBuilder->CurrentActiveScrolledRoot(),
+      false);
+  if (!wrapList) {
+    return nullptr;
+  }
+  wrapList->SetOverrideZIndex(
+      std::numeric_limits<decltype(wrapList->ZIndex())>::max());
+  return wrapList;
+}
+
+#ifdef DEBUG
+void ViewportFrame::AppendFrames(ChildListID aListID,
+                                 nsFrameList&& aFrameList) {
+  NS_ASSERTION(aListID == FrameChildListID::Principal, "unexpected child list");
+  NS_ASSERTION(GetChildList(aListID).IsEmpty(), "Shouldn't have any kids!");
+  nsContainerFrame::AppendFrames(aListID, std::move(aFrameList));
+}
+
+void ViewportFrame::InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
+                                 const nsLineList::iterator* aPrevFrameLine,
+                                 nsFrameList&& aFrameList) {
+  NS_ASSERTION(aListID == FrameChildListID::Principal, "unexpected child list");
+  NS_ASSERTION(GetChildList(aListID).IsEmpty(), "Shouldn't have any kids!");
+  nsContainerFrame::InsertFrames(aListID, aPrevFrame, aPrevFrameLine,
+                                 std::move(aFrameList));
+}
+
+void ViewportFrame::RemoveFrame(DestroyContext& aContext, ChildListID aListID,
+                                nsIFrame* aOldFrame) {
+  NS_ASSERTION(aListID == FrameChildListID::Principal, "unexpected child list");
+  nsContainerFrame::RemoveFrame(aContext, aListID, aOldFrame);
+}
+#endif
+
+/* virtual */
+nscoord ViewportFrame::GetMinISize(gfxContext* aRenderingContext) {
+  nscoord result;
+  DISPLAY_MIN_INLINE_SIZE(this, result);
+  if (mFrames.IsEmpty())
+    result = 0;
+  else
+    result = mFrames.FirstChild()->GetMinISize(aRenderingContext);
+
+  return result;
+}
+
+/* virtual */
+nscoord ViewportFrame::GetPrefISize(gfxContext* aRenderingContext) {
+  nscoord result;
+  DISPLAY_PREF_INLINE_SIZE(this, result);
+  if (mFrames.IsEmpty())
+    result = 0;
+  else
+    result = mFrames.FirstChild()->GetPrefISize(aRenderingContext);
+
+  return result;
+}
+
+nsPoint ViewportFrame::AdjustReflowInputForScrollbars(
+    ReflowInput* aReflowInput) const {
+  // Get our prinicpal child frame and see if we're scrollable
+  nsIFrame* kidFrame = mFrames.FirstChild();
+  nsIScrollableFrame* scrollingFrame = do_QueryFrame(kidFrame);
+
+  if (scrollingFrame) {
+    WritingMode wm = aReflowInput->GetWritingMode();
+    LogicalMargin scrollbars(wm, scrollingFrame->GetActualScrollbarSizes());
+    aReflowInput->SetComputedISize(
+        aReflowInput->ComputedISize() - scrollbars.IStartEnd(wm),
+        ReflowInput::ResetResizeFlags::No);
+    aReflowInput->SetAvailableISize(aReflowInput->AvailableISize() -
+                                    scrollbars.IStartEnd(wm));
+    aReflowInput->SetComputedBSize(
+        aReflowInput->ComputedBSize() - scrollbars.BStartEnd(wm),
+        ReflowInput::ResetResizeFlags::No);
+    return nsPoint(scrollbars.Left(wm), scrollbars.Top(wm));
+  }
+  return nsPoint(0, 0);
+}
+
+nsRect ViewportFrame::AdjustReflowInputAsContainingBlock(
+    ReflowInput* aReflowInput) const {
+  const nsPoint origin = AdjustReflowInputForScrollbars(aReflowInput);
+  nsRect rect(origin, aReflowInput->ComputedPhysicalSize());
+  rect.SizeTo(AdjustViewportSizeForFixedPosition(rect));
+
+  return rect;
+}
+
+void ViewportFrame::Reflow(nsPresContext* aPresContext,
+                           ReflowOutput& aDesiredSize,
+                           const ReflowInput& aReflowInput,
+                           nsReflowStatus& aStatus) {
+  MarkInReflow();
+  DO_GLOBAL_REFLOW_COUNT("ViewportFrame");
+  DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
+  MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
+  NS_FRAME_TRACE_REFLOW_IN("ViewportFrame::Reflow");
+
+  // Because |Reflow| sets ComputedBSize() on the child to our
+  // ComputedBSize().
+  AddStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE);
+
+  // Set our size up front, since some parts of reflow depend on it
+  // being already set.  Note that the computed height may be
+  // unconstrained; that's ok.  Consumers should watch out for that.
+  SetSize(aReflowInput.ComputedPhysicalSize());
+
+  // Reflow the main content first so that the placeholders of the
+  // fixed-position frames will be in the right places on an initial
+  // reflow.
+  nscoord kidBSize = 0;
+  WritingMode wm = aReflowInput.GetWritingMode();
+
+  if (mFrames.NotEmpty()) {
+    // Deal with a non-incremental reflow or an incremental reflow
+    // targeted at our one-and-only principal child frame.
+    if (aReflowInput.ShouldReflowAllKids() ||
+        mFrames.FirstChild()->IsSubtreeDirty()) {
+      // Reflow our one-and-only principal child frame
+      nsIFrame* kidFrame = mFrames.FirstChild();
+      ReflowOutput kidDesiredSize(aReflowInput);
+      const WritingMode kidWM = kidFrame->GetWritingMode();
+      LogicalSize availableSpace = aReflowInput.AvailableSize(kidWM);
+      ReflowInput kidReflowInput(aPresContext, aReflowInput, kidFrame,
+                                 availableSpace);
+
+      // Reflow the frame
+      kidReflowInput.SetComputedBSize(aReflowInput.ComputedBSize());
+      ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowInput, 0, 0,
+                  ReflowChildFlags::Default, aStatus);
+      kidBSize = kidDesiredSize.BSize(wm);
+
+      FinishReflowChild(kidFrame, aPresContext, kidDesiredSize, &kidReflowInput,
+                        0, 0, ReflowChildFlags::Default);
+    } else {
+      kidBSize = LogicalSize(wm, mFrames.FirstChild()->GetSize()).BSize(wm);
+    }
+  }
+
+  NS_ASSERTION(aReflowInput.AvailableISize() != NS_UNCONSTRAINEDSIZE,
+               "shouldn't happen anymore");
+
+  // Return the max size as our desired size
+  LogicalSize maxSize(wm, aReflowInput.AvailableISize(),
+                      // Being flowed initially at an unconstrained block size
+                      // means we should return our child's intrinsic size.
+                      aReflowInput.ComputedBSize() != NS_UNCONSTRAINEDSIZE
+                          ? aReflowInput.ComputedBSize()
+                          : kidBSize);
+  aDesiredSize.SetSize(wm, maxSize);
+  aDesiredSize.SetOverflowAreasToDesiredBounds();
+
+  if (HasAbsolutelyPositionedChildren()) {
+    // Make a copy of the reflow input and change the computed width and height
+    // to reflect the available space for the fixed items
+    ReflowInput reflowInput(aReflowInput);
+
+    if (reflowInput.AvailableBSize() == NS_UNCONSTRAINEDSIZE) {
+      // We have an intrinsic-block-size document with abs-pos/fixed-pos
+      // children. Set the available block-size and computed block-size to our
+      // chosen block-size.
+      reflowInput.SetAvailableBSize(maxSize.BSize(wm));
+      // Not having border/padding simplifies things
+      NS_ASSERTION(reflowInput.ComputedPhysicalBorderPadding() == nsMargin(),
+                   "Viewports can't have border/padding");
+      reflowInput.SetComputedBSize(maxSize.BSize(wm));
+    }
+
+    nsRect rect = AdjustReflowInputAsContainingBlock(&reflowInput);
+    AbsPosReflowFlags flags =
+        AbsPosReflowFlags::CBWidthAndHeightChanged;  // XXX could be optimized
+    GetAbsoluteContainingBlock()->Reflow(this, aPresContext, reflowInput,
+                                         aStatus, rect, flags,
+                                         /* aOverflowAreas = */ nullptr);
+  }
+
+  if (mFrames.NotEmpty()) {
+    ConsiderChildOverflow(aDesiredSize.mOverflowAreas, mFrames.FirstChild());
+  }
+
+  // If we were dirty then do a repaint
+  if (HasAnyStateBits(NS_FRAME_IS_DIRTY)) {
+    InvalidateFrame();
+  }
+
+  // Clipping is handled by the document container (e.g., nsSubDocumentFrame),
+  // so we don't need to change our overflow areas.
+  FinishAndStoreOverflow(&aDesiredSize);
+
+  NS_FRAME_TRACE_REFLOW_OUT("ViewportFrame::Reflow", aStatus);
+}
+
+void ViewportFrame::UpdateStyle(ServoRestyleState& aRestyleState) {
+  RefPtr<ComputedStyle> newStyle =
+      aRestyleState.StyleSet().ResolveInheritingAnonymousBoxStyle(
+          Style()->GetPseudoType(), nullptr);
+
+  MOZ_ASSERT(!GetNextContinuation(), "Viewport has continuations?");
+  SetComputedStyle(newStyle);
+
+  UpdateStyleOfOwnedAnonBoxes(aRestyleState);
+}
+
+void ViewportFrame::AppendDirectlyOwnedAnonBoxes(
+    nsTArray<OwnedAnonBox>& aResult) {
+  if (mFrames.NotEmpty()) {
+    aResult.AppendElement(mFrames.FirstChild());
+  }
+}
+
+nsSize ViewportFrame::AdjustViewportSizeForFixedPosition(
+    const nsRect& aViewportRect) const {
+  nsSize result = aViewportRect.Size();
+
+  mozilla::PresShell* presShell = PresShell();
+  // Layout fixed position elements to the visual viewport size if and only if
+  // it has been set and it is larger than the computed size, otherwise use the
+  // computed size.
+  if (presShell->IsVisualViewportSizeSet()) {
+    if (presShell->GetDynamicToolbarState() == DynamicToolbarState::Collapsed &&
+        result < presShell->GetVisualViewportSizeUpdatedByDynamicToolbar()) {
+      // We need to use the viewport size updated by the dynamic toolbar in the
+      // case where the dynamic toolbar is completely hidden.
+      result = presShell->GetVisualViewportSizeUpdatedByDynamicToolbar();
+    } else if (result < presShell->GetVisualViewportSize()) {
+      result = presShell->GetVisualViewportSize();
+    }
+  }
+  // Expand the size to the layout viewport size if necessary.
+  const nsSize layoutViewportSize = presShell->GetLayoutViewportSize();
+  if (result < layoutViewportSize) {
+    result = layoutViewportSize;
+  }
+
+  return result;
+}
+
+#ifdef DEBUG_FRAME_DUMP
+nsresult ViewportFrame::GetFrameName(nsAString& aResult) const {
+  return MakeFrameName(u"Viewport"_ns, aResult);
+}
+#endif