[exp] cc: Introduce cc::CompositorMutator.

content/renderer/render_thread_impl.h

 // Copyright (c) 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 CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 181 matching lines @@
   bool IsZeroCopyEnabled() override;
   bool IsOneCopyEnabled() override;
   bool IsElasticOverscrollEnabled() override;
   bool UseSingleThreadScheduler() override;
   uint32 GetImageTextureTarget() override;
   scoped_refptr<base::SingleThreadTaskRunner>
   GetCompositorMainThreadTaskRunner() override;
   scoped_refptr<base::SingleThreadTaskRunner>
   GetCompositorImplThreadTaskRunner() override;
   gpu::GpuMemoryBufferManager* GetGpuMemoryBufferManager() override;
+  cc::CompositorMutator* GetCompositorMutator() override;
   RendererScheduler* GetRendererScheduler() override;
   cc::ContextProvider* GetSharedMainThreadContextProvider() override;
   scoped_ptr<cc::BeginFrameSource> CreateExternalBeginFrameSource(
       int routing_id) override;
 
   // Synchronously establish a channel to the GPU plugin if not previously
   // established or if it has been lost (for example if the GPU plugin crashed).
   // If there is a pending asynchronous request, it will be completed by the
   // time this routine returns.
   GpuChannelHost* EstablishGpuChannelSync(CauseForGpuLaunch);
@@ skipping 428 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 #if defined(COMPILER_MSVC)
 #pragma warning(pop)
 #endif
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_