BASELINE: Update chromium to 40.0.2214.28 and ninja to 1.5.3.

Change-Id: I759465284fd64d59ad120219cbe257f7402c4181
Reviewed-by: Andras Becsi <andras.becsi@theqtcompany.com>

1 files changed, 138 insertions, 111 deletions

diff --git a/chromium/cc/trees/layer_tree_host_impl.h b/chromium/cc/trees/layer_tree_host_impl.h
index fe9afc219e6..2309ef77d5f 100644
--- a/chromium/cc/trees/layer_tree_host_impl.h
+++ b/chromium/cc/trees/layer_tree_host_impl.h
@@ -31,16 +31,18 @@
 #include "cc/quads/render_pass.h"
 #include "cc/resources/resource_provider.h"
 #include "cc/resources/tile_manager.h"
+#include "cc/scheduler/begin_frame_source.h"
 #include "cc/scheduler/draw_result.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkColor.h"
-#include "ui/gfx/rect.h"
+#include "ui/gfx/geometry/rect.h"
 
 namespace cc {
 
 class CompletionEvent;
 class CompositorFrameMetadata;
 class DebugRectHistory;
+class EvictionTilePriorityQueue;
 class FrameRateCounter;
 class LayerImpl;
 class LayerTreeHostImplTimeSourceAdapter;
@@ -49,6 +51,7 @@ class MemoryHistory;
 class PageScaleAnimation;
 class PaintTimeCounter;
 class PictureLayerImpl;
+class RasterTilePriorityQueue;
 class RasterWorkerPool;
 class RenderPassDrawQuad;
 class RenderingStatsInstrumentation;
@@ -71,7 +74,6 @@ class LayerTreeHostImplClient {
   virtual void SetMaxSwapsPendingOnImplThread(int max) = 0;
   virtual void DidSwapBuffersOnImplThread() = 0;
   virtual void DidSwapBuffersCompleteOnImplThread() = 0;
-  virtual void BeginFrame(const BeginFrameArgs& args) = 0;
   virtual void OnCanDrawStateChanged(bool can_draw) = 0;
   virtual void NotifyReadyToActivate() = 0;
   // Please call these 3 functions through
@@ -94,7 +96,7 @@ class LayerTreeHostImplClient {
   virtual void PostDelayedScrollbarFadeOnImplThread(
       const base::Closure& start_fade,
       base::TimeDelta delay) = 0;
-  virtual void DidActivatePendingTree() = 0;
+  virtual void DidActivateSyncTree() = 0;
   virtual void DidManageTiles() = 0;
 
  protected:
@@ -110,6 +112,7 @@ class CC_EXPORT LayerTreeHostImpl
       public OutputSurfaceClient,
       public TopControlsManagerClient,
       public ScrollbarAnimationControllerClient,
+      public BeginFrameSourceMixIn,
       public base::SupportsWeakPtr<LayerTreeHostImpl> {
  public:
   static scoped_ptr<LayerTreeHostImpl> Create(
@@ -117,50 +120,54 @@ class CC_EXPORT LayerTreeHostImpl
       LayerTreeHostImplClient* client,
       Proxy* proxy,
       RenderingStatsInstrumentation* rendering_stats_instrumentation,
-      SharedBitmapManager* manager,
+      SharedBitmapManager* shared_bitmap_manager,
+      gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
       int id);
-  virtual ~LayerTreeHostImpl();
+  ~LayerTreeHostImpl() override;
+
+  // BeginFrameSourceMixIn implementation
+  void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
 
   // InputHandler implementation
-  virtual void BindToClient(InputHandlerClient* client) OVERRIDE;
-  virtual InputHandler::ScrollStatus ScrollBegin(
+  void BindToClient(InputHandlerClient* client) override;
+  InputHandler::ScrollStatus ScrollBegin(
+      const gfx::Point& viewport_point,
+      InputHandler::ScrollInputType type) override;
+  InputHandler::ScrollStatus ScrollAnimated(
       const gfx::Point& viewport_point,
-      InputHandler::ScrollInputType type) OVERRIDE;
-  virtual bool ScrollBy(const gfx::Point& viewport_point,
-                        const gfx::Vector2dF& scroll_delta) OVERRIDE;
-  virtual bool ScrollVerticallyByPage(const gfx::Point& viewport_point,
-                                      ScrollDirection direction) OVERRIDE;
-  virtual void SetRootLayerScrollOffsetDelegate(
-      LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) OVERRIDE;
-  virtual void OnRootLayerDelegatedScrollOffsetChanged() OVERRIDE;
-  virtual void ScrollEnd() OVERRIDE;
-  virtual InputHandler::ScrollStatus FlingScrollBegin() OVERRIDE;
-  virtual void MouseMoveAt(const gfx::Point& viewport_point) OVERRIDE;
-  virtual void PinchGestureBegin() OVERRIDE;
-  virtual void PinchGestureUpdate(float magnify_delta,
-                                  const gfx::Point& anchor) OVERRIDE;
-  virtual void PinchGestureEnd() OVERRIDE;
-  virtual void StartPageScaleAnimation(const gfx::Vector2d& target_offset,
-                                       bool anchor_point,
-                                       float page_scale,
-                                       base::TimeDelta duration) OVERRIDE;
-  virtual void SetNeedsAnimate() OVERRIDE;
-  virtual bool IsCurrentlyScrollingLayerAt(
+      const gfx::Vector2dF& scroll_delta) override;
+  InputHandlerScrollResult ScrollBy(
       const gfx::Point& viewport_point,
-      InputHandler::ScrollInputType type) OVERRIDE;
-  virtual bool HaveTouchEventHandlersAt(
-      const gfx::Point& viewport_port) OVERRIDE;
-  virtual scoped_ptr<SwapPromiseMonitor> CreateLatencyInfoSwapPromiseMonitor(
-      ui::LatencyInfo* latency) OVERRIDE;
+      const gfx::Vector2dF& scroll_delta) override;
+  bool ScrollVerticallyByPage(const gfx::Point& viewport_point,
+                              ScrollDirection direction) override;
+  void SetRootLayerScrollOffsetDelegate(
+      LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate) override;
+  void OnRootLayerDelegatedScrollOffsetChanged() override;
+  void ScrollEnd() override;
+  InputHandler::ScrollStatus FlingScrollBegin() override;
+  void MouseMoveAt(const gfx::Point& viewport_point) override;
+  void PinchGestureBegin() override;
+  void PinchGestureUpdate(float magnify_delta,
+                          const gfx::Point& anchor) override;
+  void PinchGestureEnd() override;
+  void SetNeedsAnimate() override;
+  bool IsCurrentlyScrollingLayerAt(const gfx::Point& viewport_point,
+                                   InputHandler::ScrollInputType type) override;
+  bool HaveTouchEventHandlersAt(const gfx::Point& viewport_port) override;
+  scoped_ptr<SwapPromiseMonitor> CreateLatencyInfoSwapPromiseMonitor(
+      ui::LatencyInfo* latency) override;
 
   // TopControlsManagerClient implementation.
-  virtual void DidChangeTopControlsPosition() OVERRIDE;
-  virtual bool HaveRootScrollLayer() const OVERRIDE;
+  void SetControlsTopOffset(float offset) override;
+  float ControlsTopOffset() const override;
+  void DidChangeTopControlsPosition() override;
+  bool HaveRootScrollLayer() const override;
 
   struct CC_EXPORT FrameData : public RenderPassSink {
     FrameData();
-    virtual ~FrameData();
-    scoped_ptr<base::Value> AsValue() const;
+    ~FrameData() override;
+    void AsValueInto(base::debug::TracedValue* value) const;
 
     std::vector<gfx::Rect> occluding_screen_space_rects;
     std::vector<gfx::Rect> non_occluding_screen_space_rects;
@@ -172,7 +179,7 @@ class CC_EXPORT LayerTreeHostImpl
     bool has_no_damage;
 
     // RenderPassSink implementation.
-    virtual void AppendRenderPass(scoped_ptr<RenderPass> render_pass) OVERRIDE;
+    void AppendRenderPass(scoped_ptr<RenderPass> render_pass) override;
   };
 
   virtual void BeginMainFrameAborted(bool did_handle);
@@ -213,53 +220,53 @@ class CC_EXPORT LayerTreeHostImpl
   // Resets all of the trees to an empty state.
   void ResetTreesForTesting();
 
-  bool device_viewport_valid_for_tile_management() const {
-    return device_viewport_valid_for_tile_management_;
-  }
+  DrawMode GetDrawMode() const;
 
   // Viewport size in draw space: this size is in physical pixels and is used
   // for draw properties, tilings, quads and render passes.
   gfx::Size DrawViewportSize() const;
 
-  // Viewport size for scrolling and fixed-position compensation. This value
-  // excludes the URL bar and non-overlay scrollbars and is in DIP (and
-  // invariant relative to page scale).
-  gfx::SizeF UnscaledScrollableViewportSize() const;
-  float VerticalAdjust() const;
+  // Viewport rect in view space used for tiling prioritization.
+  const gfx::Rect ViewportRectForTilePriority() const;
 
   // RendererClient implementation.
-  virtual void SetFullRootLayerDamage() OVERRIDE;
-  virtual void RunOnDemandRasterTask(Task* on_demand_raster_task) OVERRIDE;
+  void SetFullRootLayerDamage() override;
 
   // TileManagerClient implementation.
-  virtual const std::vector<PictureLayerImpl*>& GetPictureLayers() OVERRIDE;
-  virtual void NotifyReadyToActivate() OVERRIDE;
-  virtual void NotifyTileStateChanged(const Tile* tile) OVERRIDE;
+  const std::vector<PictureLayerImpl*>& GetPictureLayers() const override;
+  void NotifyReadyToActivate() override;
+  void NotifyTileStateChanged(const Tile* tile) override;
+  void BuildRasterQueue(RasterTilePriorityQueue* queue,
+                        TreePriority tree_priority) override;
+  void BuildEvictionQueue(EvictionTilePriorityQueue* queue,
+                          TreePriority tree_priority) override;
 
   // ScrollbarAnimationControllerClient implementation.
-  virtual void PostDelayedScrollbarFade(const base::Closure& start_fade,
-                                        base::TimeDelta delay) OVERRIDE;
-  virtual void SetNeedsScrollbarAnimationFrame() OVERRIDE;
+  void PostDelayedScrollbarFade(const base::Closure& start_fade,
+                                base::TimeDelta delay) override;
+  void SetNeedsScrollbarAnimationFrame() override;
 
   // OutputSurfaceClient implementation.
-  virtual void DeferredInitialize() OVERRIDE;
-  virtual void ReleaseGL() OVERRIDE;
-  virtual void CommitVSyncParameters(base::TimeTicks timebase,
-                                     base::TimeDelta interval) OVERRIDE;
-  virtual void SetNeedsRedrawRect(const gfx::Rect& rect) OVERRIDE;
-  virtual void BeginFrame(const BeginFrameArgs& args) OVERRIDE;
-  virtual void SetExternalDrawConstraints(
+  void DeferredInitialize() override;
+  void ReleaseGL() override;
+  void CommitVSyncParameters(base::TimeTicks timebase,
+                             base::TimeDelta interval) override;
+  void SetNeedsRedrawRect(const gfx::Rect& rect) override;
+  void BeginFrame(const BeginFrameArgs& args) override;
+
+  void SetExternalDrawConstraints(
       const gfx::Transform& transform,
       const gfx::Rect& viewport,
       const gfx::Rect& clip,
-      bool valid_for_tile_management) OVERRIDE;
-  virtual void DidLoseOutputSurface() OVERRIDE;
-  virtual void DidSwapBuffers() OVERRIDE;
-  virtual void DidSwapBuffersComplete() OVERRIDE;
-  virtual void ReclaimResources(const CompositorFrameAck* ack) OVERRIDE;
-  virtual void SetMemoryPolicy(const ManagedMemoryPolicy& policy) OVERRIDE;
-  virtual void SetTreeActivationCallback(const base::Closure& callback)
-      OVERRIDE;
+      const gfx::Rect& viewport_rect_for_tile_priority,
+      const gfx::Transform& transform_for_tile_priority,
+      bool resourceless_software_draw) override;
+  void DidLoseOutputSurface() override;
+  void DidSwapBuffers() override;
+  void DidSwapBuffersComplete() override;
+  void ReclaimResources(const CompositorFrameAck* ack) override;
+  void SetMemoryPolicy(const ManagedMemoryPolicy& policy) override;
+  void SetTreeActivationCallback(const base::Closure& callback) override;
 
   // Called from LayerTreeImpl.
   void OnCanDrawStateChangedForTree();
@@ -275,7 +282,6 @@ class CC_EXPORT LayerTreeHostImpl
   int SourceAnimationFrameNumber() const;
 
   virtual bool InitializeRenderer(scoped_ptr<OutputSurface> output_surface);
-  bool IsContextLost();
   TileManager* tile_manager() { return tile_manager_.get(); }
   void SetUseGpuRasterization(bool use_gpu);
   bool use_gpu_rasterization() const { return use_gpu_rasterization_; }
@@ -287,7 +293,6 @@ class CC_EXPORT LayerTreeHostImpl
   const RendererCapabilitiesImpl& GetRendererCapabilities() const;
 
   virtual bool SwapBuffers(const FrameData& frame);
-  void SetNeedsBeginFrame(bool enable);
   virtual void WillBeginImplFrame(const BeginFrameArgs& args);
   void DidModifyTilePriorities();
 
@@ -295,17 +300,15 @@ class CC_EXPORT LayerTreeHostImpl
   const LayerTreeImpl* active_tree() const { return active_tree_.get(); }
   LayerTreeImpl* pending_tree() { return pending_tree_.get(); }
   const LayerTreeImpl* pending_tree() const { return pending_tree_.get(); }
+  LayerTreeImpl* recycle_tree() { return recycle_tree_.get(); }
   const LayerTreeImpl* recycle_tree() const { return recycle_tree_.get(); }
   // Returns the tree LTH synchronizes with.
   LayerTreeImpl* sync_tree() {
-    // In impl-side painting, synchronize to the pending tree so that it has
-    // time to raster before being displayed.
-    return settings_.impl_side_painting ? pending_tree_.get()
-                                        : active_tree_.get();
+    return pending_tree_ ? pending_tree_.get() : active_tree_.get();
   }
   virtual void CreatePendingTree();
   virtual void UpdateVisibleTiles();
-  virtual void ActivatePendingTree();
+  virtual void ActivateSyncTree();
 
   // Shortcuts to layers on the active tree.
   LayerImpl* RootLayer() const;
@@ -319,8 +322,10 @@ class CC_EXPORT LayerTreeHostImpl
   bool scroll_affects_scroll_handler() const {
     return scroll_affects_scroll_handler_;
   }
+  void QueueSwapPromiseForMainThreadScrollUpdate(
+      scoped_ptr<SwapPromise> swap_promise);
 
-  bool IsCurrentlyScrolling() const;
+  bool IsActivelyScrolling() const;
 
   virtual void SetVisible(bool visible);
   bool visible() const { return visible_; }
@@ -336,9 +341,6 @@ class CC_EXPORT LayerTreeHostImpl
   void SetViewportSize(const gfx::Size& device_viewport_size);
   gfx::Size device_viewport_size() const { return device_viewport_size_; }
 
-  void SetOverdrawBottomHeight(float overdraw_bottom_height);
-  float overdraw_bottom_height() const { return overdraw_bottom_height_; }
-
   void SetOverhangUIResource(UIResourceId overhang_ui_resource_id,
                              const gfx::Size& overhang_ui_resource_size);
 
@@ -412,19 +414,26 @@ class CC_EXPORT LayerTreeHostImpl
   bool pinch_gesture_active() const { return pinch_gesture_active_; }
 
   void SetTreePriority(TreePriority priority);
+  TreePriority GetTreePriority() const;
 
-  void UpdateCurrentFrameTime();
-  void ResetCurrentFrameTimeForNextFrame();
-  virtual base::TimeTicks CurrentFrameTimeTicks();
+  void UpdateCurrentBeginFrameArgs(const BeginFrameArgs& args);
+  void ResetCurrentBeginFrameArgsForNextFrame();
+  virtual BeginFrameArgs CurrentBeginFrameArgs() const;
 
   // Expected time between two begin impl frame calls.
   base::TimeDelta begin_impl_frame_interval() const {
     return begin_impl_frame_interval_;
   }
 
-  scoped_ptr<base::Value> AsValue() const { return AsValueWithFrame(NULL); }
-  scoped_ptr<base::Value> AsValueWithFrame(FrameData* frame) const;
-  scoped_ptr<base::Value> ActivationStateAsValue() const;
+  void AsValueInto(base::debug::TracedValue* value) const override;
+  void AsValueWithFrameInto(FrameData* frame,
+                            base::debug::TracedValue* value) const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> AsValueWithFrame(
+      FrameData* frame) const;
+  scoped_refptr<base::debug::ConvertableToTraceFormat> ActivationStateAsValue()
+      const;
+  void ActivationStateAsValueInto(base::debug::TracedValue* value) const;
 
   bool page_scale_animation_active() const { return !!page_scale_animation_; }
 
@@ -465,22 +474,39 @@ class CC_EXPORT LayerTreeHostImpl
   void RegisterPictureLayerImpl(PictureLayerImpl* layer);
   void UnregisterPictureLayerImpl(PictureLayerImpl* layer);
 
+  void GetPictureLayerImplPairs(
+      std::vector<PictureLayerImpl::Pair>* layers) const;
+
+  void SetTopControlsLayoutHeight(float height);
+
+  void SetRequiresHighResToDraw() { requires_high_res_to_draw_ = true; }
+  void ResetRequiresHighResToDraw() { requires_high_res_to_draw_ = false; }
+  bool RequiresHighResToDraw() const { return requires_high_res_to_draw_; }
+
+  // Only valid for synchronous (non-scheduled) single-threaded case.
+  void SynchronouslyInitializeAllTiles();
+
+  bool CanUseZeroCopyRasterizer() const;
+  bool CanUseOneCopyRasterizer() const;
+  virtual void CreateResourceAndRasterWorkerPool(
+      scoped_ptr<RasterWorkerPool>* raster_worker_pool,
+      scoped_ptr<ResourcePool>* resource_pool,
+      scoped_ptr<ResourcePool>* staging_resource_pool);
+
  protected:
   LayerTreeHostImpl(
       const LayerTreeSettings& settings,
       LayerTreeHostImplClient* client,
       Proxy* proxy,
       RenderingStatsInstrumentation* rendering_stats_instrumentation,
-      SharedBitmapManager* manager,
+      SharedBitmapManager* shared_bitmap_manager,
+      gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
       int id);
 
-  gfx::SizeF ComputeInnerViewportContainerSize() const;
-  void UpdateInnerViewportContainerSize();
+  void UpdateViewportContainerSizes();
 
   // Virtual for testing.
   virtual void AnimateLayers(base::TimeTicks monotonic_time);
-
-  // Virtual for testing.
   virtual base::TimeDelta LowFrequencyAnimationInterval() const;
 
   const AnimationRegistrar::AnimationControllerMap&
@@ -500,14 +526,21 @@ class CC_EXPORT LayerTreeHostImpl
   void ReleaseTreeResources();
   void EnforceZeroBudget(bool zero_budget);
 
-  bool UseZeroCopyTextureUpload() const;
-  bool UseOneCopyTextureUpload() const;
+  bool UsePendingTreeForSync() const;
+  bool IsSynchronousSingleThreaded() const;
 
+  // Scroll by preferring to move the outer viewport first, only moving the
+  // inner if the outer is at its scroll extents.
   void ScrollViewportBy(gfx::Vector2dF scroll_delta);
+  // Scroll by preferring to move the inner viewport first, only moving the
+  // outer if the inner is at its scroll extents.
+  void ScrollViewportInnerFirst(gfx::Vector2dF scroll_delta);
   void AnimatePageScale(base::TimeTicks monotonic_time);
   void AnimateScrollbars(base::TimeTicks monotonic_time);
   void AnimateTopControls(base::TimeTicks monotonic_time);
 
+  bool ShouldTopControlsConsumeScroll(const gfx::Vector2dF& scroll_delta) const;
+
   gfx::Vector2dF ScrollLayerWithViewportSpaceDelta(
       LayerImpl* layer_impl,
       float scale_from_viewport_to_screen_space,
@@ -551,6 +584,7 @@ class CC_EXPORT LayerTreeHostImpl
   void MarkUIResourceNotEvicted(UIResourceId uid);
 
   void NotifySwapPromiseMonitorsOfSetNeedsRedraw();
+  void NotifySwapPromiseMonitorsOfForwardingToMainThread();
 
   typedef base::hash_map<UIResourceId, UIResourceData>
       UIResourceMap;
@@ -562,7 +596,6 @@ class CC_EXPORT LayerTreeHostImpl
   std::set<UIResourceId> evicted_ui_resources_;
 
   scoped_ptr<OutputSurface> output_surface_;
-  scoped_refptr<ContextProvider> offscreen_context_provider_;
 
   // |resource_provider_| and |tile_manager_| can be NULL, e.g. when using tile-
   // free rendering - see OutputSurface::ForcedDrawToSoftwareDevice().
@@ -574,10 +607,6 @@ class CC_EXPORT LayerTreeHostImpl
   scoped_ptr<ResourcePool> staging_resource_pool_;
   scoped_ptr<Renderer> renderer_;
 
-  TaskGraphRunner synchronous_task_graph_runner_;
-  TaskGraphRunner* on_demand_task_graph_runner_;
-  NamespaceToken on_demand_task_namespace_;
-
   GlobalStateThatImpactsTilePriority global_tile_state_;
 
   // Tree currently being drawn.
@@ -597,6 +626,7 @@ class CC_EXPORT LayerTreeHostImpl
   bool wheel_scrolling_;
   bool scroll_affects_scroll_handler_;
   int scroll_layer_id_when_mouse_over_scrollbar_;
+  ScopedPtrVector<SwapPromise> swap_promises_for_main_thread_scroll_update_;
 
   bool tile_priorities_dirty_;
 
@@ -647,25 +677,22 @@ class CC_EXPORT LayerTreeHostImpl
   UIResourceId overhang_ui_resource_id_;
   gfx::Size overhang_ui_resource_size_;
 
-  // Vertical amount of the viewport size that's known to covered by a
-  // browser-side UI element, such as an on-screen-keyboard.  This affects
-  // scrollable size since we want to still be able to scroll to the bottom of
-  // the page when the keyboard is up.
-  float overdraw_bottom_height_;
-
   // Optional top-level constraints that can be set by the OutputSurface.
   // - external_transform_ applies a transform above the root layer
   // - external_viewport_ is used DrawProperties, tile management and
   // glViewport/window projection matrix.
   // - external_clip_ specifies a top-level clip rect
+  // - viewport_rect_for_tile_priority_ is the rect in view space used for
+  // tiling priority.
   gfx::Transform external_transform_;
   gfx::Rect external_viewport_;
   gfx::Rect external_clip_;
-  bool device_viewport_valid_for_tile_management_;
+  gfx::Rect viewport_rect_for_tile_priority_;
+  bool resourceless_software_draw_;
 
   gfx::Rect viewport_damage_rect_;
 
-  base::TimeTicks current_frame_timeticks_;
+  BeginFrameArgs current_begin_frame_args_;
 
   // Expected time between two begin impl frame calls.
   base::TimeDelta begin_impl_frame_interval_;
@@ -674,23 +701,23 @@ class CC_EXPORT LayerTreeHostImpl
 
   RenderingStatsInstrumentation* rendering_stats_instrumentation_;
   MicroBenchmarkControllerImpl micro_benchmark_controller_;
+  scoped_ptr<TaskGraphRunner> single_thread_synchronous_task_graph_runner_;
 
   bool need_to_update_visible_tiles_before_draw_;
-#if DCHECK_IS_ON
-  bool did_lose_called_;
-#endif
 
   // Optional callback to notify of new tree activations.
   base::Closure tree_activation_callback_;
 
   SharedBitmapManager* shared_bitmap_manager_;
+  gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager_;
   int id_;
 
   std::set<SwapPromiseMonitor*> swap_promise_monitor_;
 
-  size_t transfer_buffer_memory_limit_;
-
   std::vector<PictureLayerImpl*> picture_layers_;
+  std::vector<PictureLayerImpl::Pair> picture_layer_pairs_;
+
+  bool requires_high_res_to_draw_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };