Bug 1622360 - Remove the nsDisplayRenderRoot display item type. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D67616

--HG--
extra : moz-landing-system : lando

gfx/layers/wr/WebRenderCommandBuilder.cpp

@@ -1244,7 +1244,6 @@ void Grouper::ConstructGroups(nsDisplayListBuilder* aDisplayListBuilder,
                              item);
 
       {
-        MOZ_ASSERT(item->GetType() != DisplayItemType::TYPE_RENDER_ROOT);
         auto spaceAndClipChain = mClipManager.SwitchItem(item);
         wr::SpaceAndClipChainHelper saccHelper(aBuilder, spaceAndClipChain);
 

layout/painting/nsDisplayItemTypesList.h

@@ -65,8 +65,6 @@ DECLARE_DISPLAY_ITEM_TYPE(PLUGIN_READBACK, 0)
 DECLARE_DISPLAY_ITEM_TYPE(PRINT_PLUGIN, 0)
 DECLARE_DISPLAY_ITEM_TYPE(RANGE_FOCUS_RING, 0)
 DECLARE_DISPLAY_ITEM_TYPE(REMOTE, TYPE_RENDERS_NO_IMAGES)
-DECLARE_DISPLAY_ITEM_TYPE(RENDER_ROOT,
-                          TYPE_RENDERS_NO_IMAGES | TYPE_IS_CONTAINER)
 DECLARE_DISPLAY_ITEM_TYPE(RESOLUTION,
                           TYPE_RENDERS_NO_IMAGES | TYPE_IS_CONTAINER)
 DECLARE_DISPLAY_ITEM_TYPE(SCROLL_INFO_LAYER,

layout/painting/nsDisplayList.cpp

@@ -1174,7 +1174,6 @@ nsDisplayListBuilder::nsDisplayListBuilder(nsIFrame* aReferenceFrame,
       mCurrentContainerASR(nullptr),
       mCurrentFrame(aReferenceFrame),
       mCurrentReferenceFrame(aReferenceFrame),
-      mNeedsDisplayListBuild{},
       mRootAGR(AnimatedGeometryRoot::CreateAGRForFrame(
           aReferenceFrame, nullptr, true, aRetainingDisplayList)),
       mCurrentAGR(mRootAGR),
@@ -1266,9 +1265,6 @@ void nsDisplayListBuilder::BeginFrame() {
   mInTransform = false;
   mInFilter = false;
   mSyncDecodeImages = false;
-  for (auto& needsDisplayListBuild : mNeedsDisplayListBuild) {
-    needsDisplayListBuild = false;
-  }
 
   for (auto& renderRootRect : mRenderRootRects) {
     renderRootRect = LayoutDeviceRect();
@@ -7057,127 +7053,6 @@ void nsDisplayOwnLayer::WriteDebugInfo(std::stringstream& aStream) {
                  .get();
 }
 
-nsDisplayRenderRoot::nsDisplayRenderRoot(
-    nsDisplayListBuilder* aBuilder, nsIFrame* aFrame, nsDisplayList* aList,
-    const ActiveScrolledRoot* aActiveScrolledRoot, wr::RenderRoot aRenderRoot)
-    : nsDisplayWrapList(aBuilder, aFrame, aList, aActiveScrolledRoot, true),
-      mRenderRoot(aRenderRoot),
-      mBuiltWRCommands(false) {
-  MOZ_ASSERT(aRenderRoot != wr::RenderRoot::Default);
-  MOZ_ASSERT(false);
-  ExpandDisplayListBuilderRenderRootRect(aBuilder);
-  MOZ_COUNT_CTOR(nsDisplayRenderRoot);
-}
-
-void nsDisplayRenderRoot::Destroy(nsDisplayListBuilder* aBuilder) {
-  if (mBuiltWRCommands && aBuilder) {
-    aBuilder->SetNeedsDisplayListBuild(mRenderRoot);
-  }
-  nsDisplayWrapList::Destroy(aBuilder);
-}
-
-void nsDisplayRenderRoot::NotifyUsed(nsDisplayListBuilder* aBuilder) {
-  ExpandDisplayListBuilderRenderRootRect(aBuilder);
-  nsDisplayWrapList::SetReused(aBuilder);
-}
-
-void nsDisplayRenderRoot::InvalidateCachedChildInfo(
-    nsDisplayListBuilder* aBuilder) {
-  if (mBuiltWRCommands && aBuilder) {
-    aBuilder->SetNeedsDisplayListBuild(mRenderRoot);
-    mBuiltWRCommands = false;
-  }
-}
-
-bool nsDisplayRenderRoot::UpdateScrollData(
-    mozilla::layers::WebRenderScrollData* aData,
-    mozilla::layers::WebRenderLayerScrollData* aLayerData) {
-  // Ideally we'd return false if this nsDisplayRenderRoot isn't actually
-  // establishing a render root boundary (i.e. if mRenderRoot ==
-  // aBuilder.GetRenderRoot()). But we don't have aBuilder here so we can't do
-  // that. Returning true unconditionally is suboptimal but still correct.
-  if (aLayerData) {
-    if (mBoundary) {
-      // Scroll data entries that are referents should never have direct
-      // descendants. Instead they will refer to a different subtree
-      MOZ_ASSERT(aLayerData->GetDescendantCount() == 0);
-      aLayerData->SetReferentRenderRoot(*mBoundary);
-    }
-  }
-  return true;
-}
-
-bool nsDisplayRenderRoot::CreateWebRenderCommands(
-    mozilla::wr::DisplayListBuilder& aBuilder,
-    mozilla::wr::IpcResourceUpdateQueue& aResources,
-    const StackingContextHelper& aSc, RenderRootStateManager* aManager,
-    nsDisplayListBuilder* aDisplayListBuilder) {
-  // It's important to get the userData here even in the early-return case,
-  // because this has the important side-effect of marking the user data "used"
-  // so it doesn't get discarded at the end of the transaction.
-  RefPtr<WebRenderRenderRootData> userData =
-      aManager->CommandBuilder()
-          .CreateOrRecycleWebRenderUserData<WebRenderRenderRootData>(
-              this, aBuilder.GetRenderRoot());
-  // Technically the next line is redundant but maybe it will stop people who
-  // don't read comments from accidentally moving the above line of code back
-  // down below the early-return.
-  userData->SetUsed(true);
-
-  if (!aDisplayListBuilder->GetNeedsDisplayListBuild(mRenderRoot) &&
-      mBuiltWRCommands) {
-    return true;
-  }
-  if (aBuilder.GetRenderRoot() == mRenderRoot) {
-    nsDisplayWrapList::CreateWebRenderCommands(aBuilder, aResources, aSc,
-                                               aManager, aDisplayListBuilder);
-  } else {
-    mBoundary = Some(userData->EnsureHasBoundary(mRenderRoot));
-
-    WebRenderCommandBuilder::ScrollDataBoundaryWrapper wrapper(
-        aManager->CommandBuilder(), *mBoundary);
-
-    aBuilder.SetSendSubBuilderDisplayList(mRenderRoot);
-    wr::DisplayListBuilder& builder = aBuilder.SubBuilder(mRenderRoot);
-    wr::IpcResourceUpdateQueue& resources = aResources.SubQueue(mRenderRoot);
-
-    wr::StackingContextParams params;
-    params.clip =
-        wr::WrStackingContextClip::ClipChain(builder.CurrentClipChainId());
-    LayoutDeviceRect rrRect =
-        aDisplayListBuilder->GetRenderRootRect(mRenderRoot);
-    LayoutDevicePoint scOrigin = aSc.GetOrigin();
-    // Subtract the render root rect from this, as it already acts as the
-    // origin for our whole display list in WebRender (via SetDocumentView).
-    // However, we can't simply ignore the value of aSc.GetOrigin(), even
-    // though they will often be the same. This is because there might be
-    // multiple cousin nsDisplayRenderRoots in a tree of nsDisplayItems, and
-    // the RenderRootRect will be the union of their areas.
-    scOrigin.x -= rrRect.x;
-    scOrigin.y -= rrRect.y;
-    StackingContextHelper sc(
-        aManager->CommandBuilder().GetRootStackingContextHelper(mRenderRoot),
-        nullptr, nullptr, nullptr, builder, params,
-        LayoutDeviceRect(scOrigin, LayoutDeviceSize()));
-
-    nsDisplayWrapList::CreateWebRenderCommands(builder, resources, sc, aManager,
-                                               aDisplayListBuilder);
-  }
-  mBuiltWRCommands = true;
-  return true;
-}
-
-void nsDisplayRenderRoot::ExpandDisplayListBuilderRenderRootRect(
-    nsDisplayListBuilder* aBuilder) {
-  if (mFrame->GetRect().IsEmpty()) {
-    return;
-  }
-  mozilla::LayoutDeviceRect rect = mozilla::LayoutDeviceRect::FromAppUnits(
-      mFrame->GetRectRelativeToSelf() + ToReferenceFrame(),
-      mFrame->PresContext()->AppUnitsPerDevPixel());
-  aBuilder->ExpandRenderRootRect(rect, mRenderRoot);
-}
-
 nsDisplaySubDocument::nsDisplaySubDocument(nsDisplayListBuilder* aBuilder,
                                            nsIFrame* aFrame,
                                            nsSubDocumentFrame* aSubDocFrame,

layout/painting/nsDisplayList.h

@@ -923,23 +923,11 @@ class nsDisplayListBuilder {
   void SubtractFromVisibleRegion(nsRegion* aVisibleRegion,
                                  const nsRegion& aRegion);
 
-  void SetNeedsDisplayListBuild(mozilla::wr::RenderRoot aRenderRoot) {
-    MOZ_ASSERT(aRenderRoot != mozilla::wr::RenderRoot::Default);
-    mNeedsDisplayListBuild[aRenderRoot] = true;
-  }
-
   void ExpandRenderRootRect(LayoutDeviceRect aRect,
                             mozilla::wr::RenderRoot aRenderRoot) {
     mRenderRootRects[aRenderRoot] = mRenderRootRects[aRenderRoot].Union(aRect);
   }
 
-  bool GetNeedsDisplayListBuild(mozilla::wr::RenderRoot aRenderRoot) {
-    if (aRenderRoot == mozilla::wr::RenderRoot::Default) {
-      return true;
-    }
-    return mNeedsDisplayListBuild[aRenderRoot];
-  }
-
   void ComputeDefaultRenderRootRect(LayoutDeviceIntSize aClientSize);
 
   LayoutDeviceRect GetRenderRootRect(mozilla::wr::RenderRoot aRenderRoot) {
@@ -1919,7 +1907,6 @@ class nsDisplayListBuilder {
   nsPoint mCurrentOffsetToReferenceFrame;
 
   mozilla::wr::RenderRootArray<LayoutDeviceRect> mRenderRootRects;
-  mozilla::wr::NonDefaultRenderRootArray<bool> mNeedsDisplayListBuild;
 
   RefPtr<AnimatedGeometryRoot> mRootAGR;
   RefPtr<AnimatedGeometryRoot> mCurrentAGR;
@@ -6128,43 +6115,6 @@ class nsDisplayOwnLayer : public nsDisplayWrapList {
   uint16_t mIndex;
 };
 
-class nsDisplayRenderRoot : public nsDisplayWrapList {
-  nsDisplayRenderRoot(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
-                      nsDisplayList* aList,
-                      const ActiveScrolledRoot* aActiveScrolledRoot,
-                      mozilla::wr::RenderRoot aRenderRoot);
-
-  MOZ_COUNTED_DTOR_OVERRIDE(nsDisplayRenderRoot)
-
-  NS_DISPLAY_DECL_NAME("RenderRoot", TYPE_RENDER_ROOT)
-
-  void InvalidateCachedChildInfo(nsDisplayListBuilder* aBuilder) override;
-  void Destroy(nsDisplayListBuilder* aBuilder) override;
-  void NotifyUsed(nsDisplayListBuilder* aBuilder) override;
-
-  bool UpdateScrollData(
-      mozilla::layers::WebRenderScrollData* aData,
-      mozilla::layers::WebRenderLayerScrollData* aLayerData) override;
-
-  bool ShouldFlattenAway(nsDisplayListBuilder* aBuilder) override {
-    return false;
-  }
-
-  bool CreateWebRenderCommands(
-      mozilla::wr::DisplayListBuilder& aBuilder,
-      mozilla::wr::IpcResourceUpdateQueue& aResources,
-      const StackingContextHelper& aSc,
-      mozilla::layers::RenderRootStateManager* aManager,
-      nsDisplayListBuilder* aDisplayListBuilder) override;
-
- protected:
-  void ExpandDisplayListBuilderRenderRootRect(nsDisplayListBuilder* aBuilder);
-
-  mozilla::wr::RenderRoot mRenderRoot;
-  bool mBuiltWRCommands;
-  mozilla::Maybe<mozilla::layers::RenderRootBoundary> mBoundary;
-};
-
 /**
  * A display item for subdocuments. This is more or less the same as
  * nsDisplayOwnLayer, except that it always populates the FrameMetrics instance