cc: GPU rasterize tiles synchronously in PrepareToDraw.

cc/resources/gpu_tile_task_worker_pool.h

Index: cc/resources/gpu_tile_task_worker_pool.h
diff --git a/cc/resources/gpu_tile_task_worker_pool.h b/cc/resources/gpu_tile_task_worker_pool.h
index 363b0a62ec150152eef5a05dde05b8d56d88f215..d50bd21e2ddd664a14631e5644d7bbc5f0787941 100644
--- a/cc/resources/gpu_tile_task_worker_pool.h
+++ b/cc/resources/gpu_tile_task_worker_pool.h
@@ -22,6 +22,7 @@ class CC_EXPORT GpuTileTaskWorkerPool : public TileTaskWorkerPool,
 
   static scoped_ptr<TileTaskWorkerPool> Create(
       base::SequencedTaskRunner* task_runner,
+      TaskGraphRunner* task_graph_runner,
       ContextProvider* context_provider,
       ResourceProvider* resource_provider,
       bool use_distance_field_text);
@@ -42,17 +43,16 @@ class CC_EXPORT GpuTileTaskWorkerPool : public TileTaskWorkerPool,
 
  private:
   GpuTileTaskWorkerPool(base::SequencedTaskRunner* task_runner,
+                        TaskGraphRunner* task_graph_runner,
                         ContextProvider* context_provider,
                         ResourceProvider* resource_provider,
                         bool use_distance_field_text);
 
   void OnTaskSetFinished(TaskSet task_set);
-  void ScheduleRunTasksOnOriginThread();
-  void RunTasksOnOriginThread();
-  void RunTaskOnOriginThread(TileTask* task);
+  void CompleteTasks(const Task::Vector& tasks);
 
   scoped_refptr<base::SequencedTaskRunner> task_runner_;
-  scoped_ptr<TaskGraphRunner> task_graph_runner_;
+  TaskGraphRunner* task_graph_runner_;
   const NamespaceToken namespace_token_;
   TileTaskRunnerClient* client_;
   ContextProvider* context_provider_;