Add the UI compositor to the Mac build

content/browser/aura/gpu_browser_compositor_output_surface.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 CONTENT_BROWSER_AURA_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
-#define CONTENT_BROWSER_AURA_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
-
-#include "content/browser/aura/browser_compositor_output_surface.h"
-
-namespace content {
-
-// Adapts a WebGraphicsContext3DCommandBufferImpl into a
-// cc::OutputSurface that also handles vsync parameter updates
-// arriving from the GPU process.
-class GpuBrowserCompositorOutputSurface
-    : public BrowserCompositorOutputSurface {
- public:
-  GpuBrowserCompositorOutputSurface(
-      const scoped_refptr<ContextProviderCommandBuffer>& context,
-      int surface_id,
-      IDMap<BrowserCompositorOutputSurface>* output_surface_map,
-      base::MessageLoopProxy* compositor_message_loop,
-      base::WeakPtr<ui::Compositor> compositor);
-
-  virtual ~GpuBrowserCompositorOutputSurface();
-
- private:
-  // cc::OutputSurface implementation.
-  virtual void SwapBuffers(cc::CompositorFrame* frame) OVERRIDE;
-
-  DISALLOW_COPY_AND_ASSIGN(GpuBrowserCompositorOutputSurface);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_AURA_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_