Re-land: cc: Examine layers to determine if we're ready to activate.

cc/resources/tile_manager.h

Index: cc/resources/tile_manager.h
diff --git a/cc/resources/tile_manager.h b/cc/resources/tile_manager.h
index cdc7d1edd10248265a4331702d93ca7d2767f789..0881e6f6ff1e4a4b556b7ce8830c276c1a8c5ae7 100644
--- a/cc/resources/tile_manager.h
+++ b/cc/resources/tile_manager.h
@@ -30,8 +30,15 @@ class ResourceProvider;
 
 class CC_EXPORT TileManagerClient {
  public:
+  // Called when all tiles marked as required for activation are ready to draw.
   virtual void NotifyReadyToActivate() = 0;
-  virtual void NotifyTileInitialized(const Tile* tile) = 0;
+
+  // Called when the visible representation of a tile might have changed. Some
+  // examples are:
+  // - Tile version initialized.
+  // - Tile resources freed.
+  // - Tile marked for on-demand raster.
+  virtual void NotifyTileStateChanged(const Tile* tile) = 0;
 
  protected:
   virtual ~TileManagerClient() {}
@@ -154,9 +161,9 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
   static scoped_ptr<TileManager> Create(
       TileManagerClient* client,
+      base::SequencedTaskRunner* task_runner,
       ResourcePool* resource_pool,
       Rasterizer* rasterizer,
-      bool use_rasterize_on_demand,
       RenderingStatsInstrumentation* rendering_stats_instrumentation);
   virtual ~TileManager();
 
@@ -228,9 +235,9 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
  protected:
   TileManager(TileManagerClient* client,
+              base::SequencedTaskRunner* task_runner,
               ResourcePool* resource_pool,
               Rasterizer* rasterizer,
-              bool use_rasterize_on_demand,
               RenderingStatsInstrumentation* rendering_stats_instrumentation);
 
   // Methods called by Tile
@@ -276,6 +283,7 @@ class CC_EXPORT TileManager : public RasterizerClient,
   void FreeResourceForTile(Tile* tile, RasterMode mode);
   void FreeResourcesForTile(Tile* tile);
   void FreeUnusedResourcesForTile(Tile* tile);
+  void FreeResourcesForTileAndNotifyClientIfTileWasReadyToDraw(Tile* tile);
   scoped_refptr<ImageDecodeTask> CreateImageDecodeTask(Tile* tile,
                                                        SkPixelRef* pixel_ref);
   scoped_refptr<RasterTask> CreateRasterTask(Tile* tile);
@@ -283,7 +291,12 @@ class CC_EXPORT TileManager : public RasterizerClient,
   void UpdatePrioritizedTileSetIfNeeded();
   void CleanUpLayers();
 
+  bool IsReadyToActivate() const;
+  void ScheduleCheckIfReadyToActivate();
+  void CheckIfReadyToActivate();
+
   TileManagerClient* client_;
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
   ResourcePool* resource_pool_;
   Rasterizer* rasterizer_;
   GlobalStateThatImpactsTilePriority global_state_;
@@ -323,8 +336,6 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
   std::vector<Tile*> released_tiles_;
 
-  bool use_rasterize_on_demand_;
-
   ResourceFormat resource_format_;
 
   // Queue used when scheduling raster tasks.
@@ -334,6 +345,10 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
   std::vector<PictureLayerImpl*> layers_;
 
+  bool check_if_ready_to_activate_pending_;
+
+  base::WeakPtrFactory<TileManager> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(TileManager);
 };