cc: Reuse the same TaskGraph and completed tasks vector.

cc/resources/image_raster_worker_pool.h

 // Copyright 2013 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_RESOURCES_IMAGE_RASTER_WORKER_POOL_H_
 #define CC_RESOURCES_IMAGE_RASTER_WORKER_POOL_H_
 
 #include "cc/resources/raster_worker_pool.h"
 
 namespace cc {
@@ skipping 32 matching lines @@
   virtual void OnRasterTasksFinished() OVERRIDE;
   virtual void OnRasterTasksRequiredForActivationFinished() OVERRIDE;
 
   scoped_ptr<base::Value> StateAsValue() const;
 
   const unsigned texture_target_;
 
   bool raster_tasks_pending_;
   bool raster_tasks_required_for_activation_pending_;
 
+  // Task graph used when scheduling tasks and vector used to gather
+  // completed tasks.
+  internal::TaskGraph graph_;
+  internal::Task::Vector completed_tasks_;
+
   DISALLOW_COPY_AND_ASSIGN(ImageRasterWorkerPool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_IMAGE_RASTER_WORKER_POOL_H_