Add the UI compositor to the Mac build

content/browser/aura/browser_compositor_output_surface_proxy.h

-// Copyright (c) 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_BROWSER_COMPOSITOR_OUTPUT_SURFACE_PROXY_H_
-#define CONTENT_BROWSER_AURA_BROWSER_COMPOSITOR_OUTPUT_SURFACE_PROXY_H_
-
-#include "base/id_map.h"
-#include "base/memory/ref_counted.h"
-#include "base/time/time.h"
-#include "content/common/content_export.h"
-
-namespace base { class SingleThreadTaskRunner; }
-
-namespace IPC { class Message; }
-
-namespace content {
-class BrowserCompositorOutputSurface;
-
-// Directs vsync updates to the appropriate BrowserCompositorOutputSurface.
-class CONTENT_EXPORT BrowserCompositorOutputSurfaceProxy
-    : public base::RefCountedThreadSafe<BrowserCompositorOutputSurfaceProxy> {
- public:
-  BrowserCompositorOutputSurfaceProxy(
-      IDMap<BrowserCompositorOutputSurface>* surface_map);
-
-  // Call this before each OutputSurface is created to ensure that the
-  // proxy is connected to the current host.
-  void ConnectToGpuProcessHost(
-      base::SingleThreadTaskRunner* compositor_thread_task_runner);
-
- private:
-  friend class base::RefCountedThreadSafe<BrowserCompositorOutputSurfaceProxy>;
-  friend class SoftwareBrowserCompositorOutputSurface;
-  ~BrowserCompositorOutputSurfaceProxy();
-
-  void OnMessageReceivedOnCompositorThread(const IPC::Message& message);
-
-  void OnUpdateVSyncParametersOnCompositorThread(int surface_id,
-                                                 base::TimeTicks timebase,
-                                                 base::TimeDelta interval);
-
-  IDMap<BrowserCompositorOutputSurface>* surface_map_;
-  int connected_to_gpu_process_host_id_;
-
-  DISALLOW_COPY_AND_ASSIGN(BrowserCompositorOutputSurfaceProxy);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_AURA_BROWSER_COMPOSITOR_OUTPUT_SURFACE_PROXY_H_