Remove GraphicsLayer::GetPosition and SetPosition

The last remaining use of GraphicsLayer's position, including
side-effects such as non-UI code reads of cc Layer::position which is
set via GraphicsLayer::SetPosition, is UpdateMainGraphicsLayerGeometry
where it is used to determine if the position changed and a call to
SetPosition is needed.  Since there are no other readers of this data,
this callsite can be removed along with all other SetPosition callsites
and supporting (now unused) code.  This has no functional impact on
Blink composition as layer position has already moved over to using
BGPT.

Bug: 999336
Change-Id: I7937c601269bafb515ad1ce16231dbacf70b8efb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1935499
Commit-Queue: Sam Fortiner <samfort@microsoft.com>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719316}

third_party/blink/renderer/core/paint/compositing/composited_layer_mapping.h

@@ -98,9 +98,7 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
       const PaintLayer* compositing_container);
   void UpdateGraphicsLayerGeometry(
       const PaintLayer* compositing_container,
-      const PaintLayer* compositing_stacking_context,
-      Vector<PaintLayer*>& layers_needing_paint_invalidation,
-      GraphicsLayerUpdater::UpdateContext& update_context);
+      Vector<PaintLayer*>& layers_needing_paint_invalidation);
 
   // Update whether background paints onto scrolling contents layer.
   // Returns (through the reference params) what invalidations are needed.
@@ -306,26 +304,19 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
       const PaintLayer* compositing_container,
       IntPoint& graphics_layer_parent_location);
   void UpdateSquashingLayerGeometry(
-      const IntPoint& graphics_layer_parent_location,
       const PaintLayer* compositing_container,
       const IntPoint& snapped_offset_from_composited_ancestor,
       Vector<GraphicsLayerPaintInfo>& layers,
       Vector<PaintLayer*>& layers_needing_paint_invalidation);
-  void UpdateMainGraphicsLayerGeometry(
-      const IntRect& relative_compositing_bounds,
-      const IntRect& local_compositing_bounds,
-      const IntPoint& graphics_layer_parent_location,
-      GraphicsLayerUpdater::UpdateContext& update_context);
+  void UpdateMainGraphicsLayerGeometry(const IntRect& local_compositing_bounds);
   void UpdateOverflowControlsHostLayerGeometry(
-      const PaintLayer* compositing_stacking_context,
-      const PaintLayer* compositing_container,
-      IntPoint graphics_layer_parent_location);
+      const PaintLayer* compositing_container);
   void UpdateChildTransformLayerGeometry();
   void UpdateMaskLayerGeometry();
   void UpdateForegroundLayerGeometry();
   void UpdateDecorationOutlineLayerGeometry(
       const IntSize& relative_compositing_bounds_size);
-  void UpdateScrollingLayerGeometry(const IntRect& local_compositing_bounds);
+  void UpdateScrollingLayerGeometry();
 
   void CreatePrimaryGraphicsLayer();
   void DestroyGraphicsLayers();
@@ -364,8 +355,6 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
   void ComputeBoundsOfOwningLayer(
       const PaintLayer* composited_ancestor,
       IntRect& local_compositing_bounds,
-      IntRect& compositing_bounds_relative_to_composited_ancestor,
-      PhysicalOffset& offset_from_composited_ancestor,
       IntPoint& snapped_offset_from_composited_ancestor);
 
   GraphicsLayerPaintingPhase PaintingPhaseForPrimaryLayer() const;
@@ -388,7 +377,6 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
   Color LayoutObjectBackgroundColor() const;
   void UpdateBackgroundColor();
   void UpdateContentsRect();
-  void UpdateAfterPartResize();
   void UpdateCompositingReasons();
 
   static bool HasVisibleNonCompositingDescendant(PaintLayer* parent);
@@ -413,9 +401,6 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
   // that layer does not appear earlier in the set of layers for this object.
   bool InvalidateLayerIfNoPrecedingEntry(wtf_size_t);
 
-  // Main GraphicsLayer of the CLM for the iframe's content document.
-  GraphicsLayer* FrameContentsGraphicsLayer() const;
-
   PaintLayer& owning_layer_;
 
   // The hierarchy of layers that is maintained by the CompositedLayerMapping

third_party/blink/renderer/core/paint/compositing/graphics_layer_updater.cc

@@ -133,9 +133,8 @@ void GraphicsLayerUpdater::UpdateRecursive(
         if (had_scrolling_layer != !!mapping->ScrollingLayer())
           layers_needing_paint_invalidation.push_back(&layer);
       }
-      mapping->UpdateGraphicsLayerGeometry(
-          compositing_container, context.CompositingStackingContext(),
-          layers_needing_paint_invalidation, context);
+      mapping->UpdateGraphicsLayerGeometry(compositing_container,
+                                           layers_needing_paint_invalidation);
       if (PaintLayerScrollableArea* scrollable_area = layer.GetScrollableArea())
         scrollable_area->PositionOverflowControls();
       update_type = mapping->UpdateTypeForChildren(update_type);

third_party/blink/renderer/core/paint/compositing/paint_layer_compositor.cc

@@ -319,17 +319,6 @@ GraphicsLayer* PaintLayerCompositor::OverlayFullscreenVideoGraphicsLayer()
   return video->Layer()->GetCompositedLayerMapping()->MainGraphicsLayer();
 }
 
-void PaintLayerCompositor::AdjustOverlayFullscreenVideoPosition(
-    GraphicsLayer* video_layer) {
-  if (!video_layer)
-    return;
-  // The fullscreen video has layer position equal to its enclosing frame's
-  // scroll position because fullscreen container is fixed-positioned.
-  // We should reset layer position here since it is attached at the
-  // very top level.
-  video_layer->SetPosition(FloatPoint());
-}
-
 void PaintLayerCompositor::UpdateWithoutAcceleratedCompositing(
     CompositingUpdateType update_type) {
   DCHECK(!HasAcceleratedCompositing());
@@ -486,7 +475,6 @@ void PaintLayerCompositor::UpdateIfNeeded(
         current_parent->SetChildren(child_list);
     }
   }
-  AdjustOverlayFullscreenVideoPosition(OverlayFullscreenVideoGraphicsLayer());
 
   for (unsigned i = 0; i < layers_needing_paint_invalidation.size(); i++) {
     ForceRecomputeVisualRectsIncludingNonCompositingDescendants(

third_party/blink/renderer/core/paint/compositing/paint_layer_compositor.h

@@ -186,7 +186,6 @@ class CORE_EXPORT PaintLayerCompositor {
 
   void EnableCompositingModeIfNeeded();
 
-  void AdjustOverlayFullscreenVideoPosition(GraphicsLayer*);
   GraphicsLayer* OverlayFullscreenVideoGraphicsLayer() const;
 
   // Checks the given graphics layer against the compositor's horizontal and

third_party/blink/renderer/platform/graphics/graphics_layer.cc

@@ -585,14 +585,6 @@ String GraphicsLayer::DebugName(const cc::Layer* layer) const {
   return "";
 }
 
-void GraphicsLayer::SetPosition(const gfx::PointF& point) {
-  CcLayer()->SetPosition(point);
-}
-
-const gfx::PointF& GraphicsLayer::GetPosition() const {
-  return CcLayer()->position();
-}
-
 const gfx::Size& GraphicsLayer::Size() const {
   return CcLayer()->bounds();
 }

third_party/blink/renderer/platform/graphics/graphics_layer.h

@@ -121,11 +121,6 @@ class PLATFORM_EXPORT GraphicsLayer : public DisplayItemClient,
   IntSize OffsetFromLayoutObject() const { return offset_from_layout_object_; }
   void SetOffsetFromLayoutObject(const IntSize&);
 
-  // The position of the layer (the location of its top-left corner in its
-  // parent).
-  const gfx::PointF& GetPosition() const;
-  void SetPosition(const gfx::PointF&);
-
   // The size of the layer.
   const gfx::Size& Size() const;
   void SetSize(const gfx::Size&);