Update from https://crrev.com/316786

cc/trees/layer_tree_impl.h

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TREES_LAYER_TREE_IMPL_H_
 #define CC_TREES_LAYER_TREE_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/containers/hash_tables.h"
 #include "base/values.h"
 #include "cc/base/scoped_ptr_vector.h"
 #include "cc/base/swap_promise.h"
 #include "cc/base/synced_property.h"
 #include "cc/layers/layer_impl.h"
 #include "cc/output/renderer.h"
 #include "cc/resources/ui_resource_client.h"
 
 namespace base {
 namespace trace_event {
 class TracedValue;
 }
-
-// TODO(ssid): remove these aliases after the tracing clients are moved to the
-// new trace_event namespace. See crbug.com/451032. ETA: March 2015
-namespace debug {
-using ::base::trace_event::TracedValue;
 }
-}  // namespace base
 
 namespace cc {
 
 class ContextProvider;
 class DebugRectHistory;
 class FrameRateCounter;
 class HeadsUpDisplayLayerImpl;
 class LayerScrollOffsetDelegateProxy;
 class LayerTreeDebugState;
 class LayerTreeHostImpl;
 class LayerTreeImpl;
 class LayerTreeSettings;
 class MemoryHistory;
 class OutputSurface;
 class PageScaleAnimation;
 class PaintTimeCounter;
 class PictureLayerImpl;
 class Proxy;
 class ResourceProvider;
 class TileManager;
 class UIResourceRequest;
 struct PendingPageScaleAnimation;
 struct RendererCapabilities;
 struct SelectionHandle;
 
 typedef std::vector<UIResourceRequest> UIResourceRequestQueue;
+typedef SyncedProperty<AdditionGroup<float>> SyncedTopControls;
 typedef SyncedProperty<AdditionGroup<gfx::Vector2dF>> SyncedElasticOverscroll;
 
 class CC_EXPORT LayerTreeImpl {
  public:
   static scoped_ptr<LayerTreeImpl> create(
       LayerTreeHostImpl* layer_tree_host_impl,
       scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor,
+      scoped_refptr<SyncedTopControls> top_controls_shown_ratio,
       scoped_refptr<SyncedElasticOverscroll> elastic_overscroll) {
-    return make_scoped_ptr(new LayerTreeImpl(
-        layer_tree_host_impl, page_scale_factor, elastic_overscroll));
+    return make_scoped_ptr(
+        new LayerTreeImpl(layer_tree_host_impl, page_scale_factor,
+                          top_controls_shown_ratio, elastic_overscroll));
   }
   virtual ~LayerTreeImpl();
 
   void Shutdown();
   void ReleaseResources();
   void RecreateResources();
 
   // Methods called by the layer tree that pass-through or access LTHI.
   // ---------------------------------------------------------------------------
   const LayerTreeSettings& settings() const;
+  const LayerTreeDebugState& debug_state() const;
   const RendererCapabilitiesImpl& GetRendererCapabilities() const;
   ContextProvider* context_provider() const;
   OutputSurface* output_surface() const;
   ResourceProvider* resource_provider() const;
   TileManager* tile_manager() const;
   FrameRateCounter* frame_rate_counter() const;
   PaintTimeCounter* paint_time_counter() const;
   MemoryHistory* memory_history() const;
   gfx::Size device_viewport_size() const;
+  float device_scale_factor() const;
+  DebugRectHistory* debug_rect_history() const;
   bool IsActiveTree() const;
   bool IsPendingTree() const;
   bool IsRecycleTree() const;
   LayerImpl* FindActiveTreeLayerById(int id);
   LayerImpl* FindPendingTreeLayerById(int id);
   bool PinchGestureActive() const;
   BeginFrameArgs CurrentBeginFrameArgs() const;
   base::TimeDelta begin_impl_frame_interval() const;
   void SetNeedsCommit();
   gfx::Rect DeviceViewport() const;
   gfx::Size DrawViewportSize() const;
   const gfx::Rect ViewportRectForTilePriority() const;
   scoped_ptr<ScrollbarAnimationController> CreateScrollbarAnimationController(
       LayerImpl* scrolling_layer);
   void DidAnimateScrollOffset();
   void InputScrollAnimationFinished();
   bool use_gpu_rasterization() const;
   GpuRasterizationStatus GetGpuRasterizationStatus() const;
   bool create_low_res_tiling() const;
   BlockingTaskRunner* BlockingMainThreadTaskRunner() const;
   bool RequiresHighResToDraw() const;
   bool SmoothnessTakesPriority() const;
 
   // Tree specific methods exposed to layer-impl tree.
   // ---------------------------------------------------------------------------
   void SetNeedsRedraw();
 
-  // TODO(nduca): These are implemented in cc files temporarily, but will become
-  // trivial accessors in a followup patch.
-  const LayerTreeDebugState& debug_state() const;
-  float device_scale_factor() const;
-  DebugRectHistory* debug_rect_history() const;
+  // Tracing methods.
+  // ---------------------------------------------------------------------------
   void GetAllTilesForTracing(std::set<const Tile*>* tiles) const;
-  void AsValueInto(base::debug::TracedValue* dict) const;
+  void AsValueInto(base::trace_event::TracedValue* dict) const;
 
   // Other public methods
   // ---------------------------------------------------------------------------
   LayerImpl* root_layer() const { return root_layer_.get(); }
   void SetRootLayer(scoped_ptr<LayerImpl>);
   scoped_ptr<LayerImpl> DetachLayerTree();
 
   void PushPropertiesTo(LayerTreeImpl* tree_impl);
 
   int source_frame_number() const { return source_frame_number_; }
@@ skipping 54 matching lines @@
   SyncedProperty<ScaleGroup>* page_scale_factor();
   const SyncedProperty<ScaleGroup>* page_scale_factor() const;
 
   SyncedElasticOverscroll* elastic_overscroll() {
     return elastic_overscroll_.get();
   }
   const SyncedElasticOverscroll* elastic_overscroll() const {
     return elastic_overscroll_.get();
   }
 
+  SyncedTopControls* top_controls_shown_ratio() {
+    return top_controls_shown_ratio_.get();
+  }
+  const SyncedTopControls* top_controls_shown_ratio() const {
+    return top_controls_shown_ratio_.get();
+  }
+
   // Updates draw properties and render surface layer list, as well as tile
   // priorities. Returns false if it was unable to update.
   bool UpdateDrawProperties();
 
   void set_needs_update_draw_properties() {
     needs_update_draw_properties_ = true;
   }
   bool needs_update_draw_properties() const {
     return needs_update_draw_properties_;
   }
 
   void set_needs_full_tree_sync(bool needs) { needs_full_tree_sync_ = needs; }
   bool needs_full_tree_sync() const { return needs_full_tree_sync_; }
 
   void ForceRedrawNextActivation() { next_activation_forces_redraw_ = true; }
 
   void set_has_ever_been_drawn(bool has_drawn) {
     has_ever_been_drawn_ = has_drawn;
   }
   bool has_ever_been_drawn() const { return has_ever_been_drawn_; }
 
   void set_ui_resource_request_queue(const UIResourceRequestQueue& queue);
 
   const LayerImplList& RenderSurfaceLayerList() const;
+  const Region& UnoccludedScreenSpaceRegion() const;
 
   // These return the size of the root scrollable area and the size of
   // the user-visible scrolling viewport, in CSS layout coordinates.
   gfx::Size ScrollableSize() const;
   gfx::SizeF ScrollableViewportSize() const;
 
   gfx::Rect RootScrollLayerDeviceViewportBounds() const;
 
   LayerImpl* LayerById(int id);
 
@@ skipping 37 matching lines @@
   void FinishSwapPromises(CompositorFrameMetadata* metadata);
   void BreakSwapPromises(SwapPromise::DidNotSwapReason reason);
 
   void DidModifyTilePriorities();
 
   ResourceProvider::ResourceId ResourceIdForUIResource(UIResourceId uid) const;
   void ProcessUIResourceRequestQueue();
 
   bool IsUIResourceOpaque(UIResourceId uid) const;
 
+  void RegisterPictureLayerImpl(PictureLayerImpl* layer);
+  void UnregisterPictureLayerImpl(PictureLayerImpl* layer);
+  const std::vector<PictureLayerImpl*>& picture_layers() const {
+    return picture_layers_;
+  }
+
   void AddLayerWithCopyOutputRequest(LayerImpl* layer);
   void RemoveLayerWithCopyOutputRequest(LayerImpl* layer);
   const std::vector<LayerImpl*>& LayersWithCopyOutputRequest() const;
 
   int current_render_surface_list_id() const {
     return render_surface_layer_list_id_;
   }
 
   LayerImpl* FindFirstScrollingLayerThatIsHitByPoint(
       const gfx::PointF& screen_space_point);
 
   LayerImpl* FindLayerThatIsHitByPoint(const gfx::PointF& screen_space_point);
 
   LayerImpl* FindLayerWithWheelHandlerThatIsHitByPoint(
       const gfx::PointF& screen_space_point);
 
   LayerImpl* FindLayerThatIsHitByPointInTouchHandlerRegion(
       const gfx::PointF& screen_space_point);
 
   void RegisterSelection(const LayerSelectionBound& start,
                          const LayerSelectionBound& end);
 
   // Compute the current selection handle location and visbility with respect to
   // the viewport.
   void GetViewportSelection(ViewportSelectionBound* start,
                             ViewportSelectionBound* end);
 
-  void RegisterPictureLayerImpl(PictureLayerImpl* layer);
-  void UnregisterPictureLayerImpl(PictureLayerImpl* layer);
-
-  void set_top_controls_shrink_blink_size(bool shrink) {
-    top_controls_shrink_blink_size_ = shrink;
-  }
-  void set_top_controls_height(float height) { top_controls_height_ = height; }
-  void set_top_controls_content_offset(float offset) {
-    top_controls_content_offset_ = offset;
-  }
-  void set_top_controls_delta(float delta) {
-    top_controls_delta_ = delta;
-  }
-  void set_sent_top_controls_delta(float sent_delta) {
-    sent_top_controls_delta_ = sent_delta;
-  }
-
+  void set_top_controls_shrink_blink_size(bool shrink);
   bool top_controls_shrink_blink_size() const {
     return top_controls_shrink_blink_size_;
   }
+  bool SetCurrentTopControlsShownRatio(float ratio);
+  float CurrentTopControlsShownRatio() const {
+    return top_controls_shown_ratio_->Current(IsActiveTree());
+  }
+  void set_top_controls_height(float top_controls_height);
   float top_controls_height() const { return top_controls_height_; }
-  float top_controls_content_offset() const {
-    return top_controls_content_offset_;
-  }
-  float top_controls_delta() const {
-    return top_controls_delta_;
-  }
-  float sent_top_controls_delta() const {
-    return sent_top_controls_delta_;
-  }
-  float total_top_controls_content_offset() const {
-    return top_controls_content_offset_ + top_controls_delta_;
-  }
+  void PushTopControlsFromMainThread(float top_controls_shown_ratio);
 
   void SetPendingPageScaleAnimation(
       scoped_ptr<PendingPageScaleAnimation> pending_animation);
   scoped_ptr<PendingPageScaleAnimation> TakePendingPageScaleAnimation();
 
  protected:
   explicit LayerTreeImpl(
       LayerTreeHostImpl* layer_tree_host_impl,
       scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor,
+      scoped_refptr<SyncedTopControls> top_controls_shown_ratio,
       scoped_refptr<SyncedElasticOverscroll> elastic_overscroll);
   void ProcessLayersRecursive(LayerImpl* current,
                               void (LayerImpl::*function)());
   float ClampPageScaleFactorToLimits(float page_scale_factor) const;
   void PushPageScaleFactorAndLimits(const float* page_scale_factor,
                                     float min_page_scale_factor,
                                     float max_page_scale_factor);
   bool SetPageScaleFactorLimits(float min_page_scale_factor,
                                 float max_page_scale_factor);
   void DidUpdatePageScale();
   void HideInnerViewportScrollbarsIfNearMinimumScale();
-
+  void PushTopControls(const float* top_controls_shown_ratio);
   LayerTreeHostImpl* layer_tree_host_impl_;
   int source_frame_number_;
   scoped_ptr<LayerImpl> root_layer_;
   HeadsUpDisplayLayerImpl* hud_layer_;
   LayerImpl* currently_scrolling_layer_;
   LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate_;
   scoped_ptr<LayerScrollOffsetDelegateProxy>
       inner_viewport_scroll_delegate_proxy_;
   scoped_ptr<LayerScrollOffsetDelegateProxy>
       outer_viewport_scroll_delegate_proxy_;
@@ skipping 10 matching lines @@
 
   scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor_;
   float min_page_scale_factor_;
   float max_page_scale_factor_;
 
   scoped_refptr<SyncedElasticOverscroll> elastic_overscroll_;
 
   typedef base::hash_map<int, LayerImpl*> LayerIdMap;
   LayerIdMap layer_id_map_;
 
+  std::vector<PictureLayerImpl*> picture_layers_;
   std::vector<LayerImpl*> layers_with_copy_output_request_;
 
   // Persisted state for non-impl-side-painting.
   int scrolling_layer_id_from_previous_tree_;
 
   // List of visible layers for the most recently prepared frame.
   LayerImplList render_surface_layer_list_;
+  // After drawing the |render_surface_layer_list_| the areas in this region
+  // would not be fully covered by opaque content.
+  Region unoccluded_screen_space_region_;
 
   bool contents_textures_purged_;
   bool viewport_size_invalid_;
   bool needs_update_draw_properties_;
 
   // In impl-side painting mode, this is true when the tree may contain
   // structural differences relative to the active tree.
   bool needs_full_tree_sync_;
 
   bool next_activation_forces_redraw_;
 
   bool has_ever_been_drawn_;
 
   ScopedPtrVector<SwapPromise> swap_promise_list_;
 
   UIResourceRequestQueue ui_resource_request_queue_;
 
   int render_surface_layer_list_id_;
 
   // Whether or not Blink's viewport size was shrunk by the height of the top
   // controls at the time of the last layout.
   bool top_controls_shrink_blink_size_;
 
   float top_controls_height_;
 
-  // The up-to-date content offset of the top controls, i.e. the amount that the
-  // web contents have been shifted down from the top of the device viewport.
-  float top_controls_content_offset_;
-  float top_controls_delta_;
-  float sent_top_controls_delta_;
+  // The amount that the top controls are shown from 0 (hidden) to 1 (fully
+  // shown).
+  scoped_refptr<SyncedTopControls> top_controls_shown_ratio_;
 
   scoped_ptr<PendingPageScaleAnimation> pending_page_scale_animation_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(LayerTreeImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_IMPL_H_