cc: Avoid expensive RenderingStats collection.

cc/raster_worker_pool.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_RASTER_WORKER_POOL_H_
 #define CC_RASTER_WORKER_POOL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/threading/thread.h"
 #include "cc/rendering_stats.h"
 #include "ui/gfx/rect.h"
 
 namespace skia {
 class LazyPixelRef;
 }
 
 namespace cc {
 class PicturePileImpl;
 
 class RasterWorkerPool {
  public:
-  explicit RasterWorkerPool(size_t num_raster_threads);
   virtual ~RasterWorkerPool();
 
-  static scoped_ptr<RasterWorkerPool> Create(size_t num_raster_threads) {
-    return make_scoped_ptr(new RasterWorkerPool(num_raster_threads));
+  static scoped_ptr<RasterWorkerPool> Create(
+      size_t num_raster_threads, bool record_rendering_stats) {
+    return make_scoped_ptr(new RasterWorkerPool(
+        num_raster_threads, record_rendering_stats));
   }
 
   // Starts the worker pool. Returns true if the worker pool was successfully
   // started; otherwise, returns false.
   bool Start();
 
   // Tells the worker pool to stop and returns once all pending tasks have
   // completed.
   void Stop();
 
   // Returns true if the worker pool has been started, and not yet stopped.
   bool IsRunning() const;
 
   bool IsBusy();
 
   void PostRasterTaskAndReply(PicturePileImpl* picture_pile,
                               uint8* buffer,
                               const gfx::Rect& rect,
                               float contents_scale,
                               const base::Closure& reply);
   void PostImageDecodeTaskAndReply(skia::LazyPixelRef* pixel_ref,
                                    const base::Closure& reply);
 
   void GetRenderingStats(RenderingStats* stats);
 
  private:
+  RasterWorkerPool(size_t num_raster_threads, bool record_rendering_stats);
+
   class Thread : public base::Thread {
    public:
     class Task {
      public:
       Task(Thread* thread);
       ~Task();
 
      private:
       friend class RasterWorkerPool;
 
@@ skipping 34 matching lines @@
                              scoped_refptr<PicturePileImpl> picture_pile,
                              const base::Closure& reply);
 
   void SortRasterThreadsIfNeeded();
 
   bool is_running_;
 
   typedef std::vector<Thread*> ThreadVector;
   ThreadVector raster_threads_;
   bool raster_threads_need_sorting_;
+  bool record_rendering_stats_;
 
   DISALLOW_COPY_AND_ASSIGN(RasterWorkerPool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RASTER_WORKER_POOL_H_