Provide real GPUSupport to ash for Chrome

ash/content_support/gpu_support_impl.h

 // Copyright 2014 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 ASH_CONTENT_SUPPORT_GPU_SUPPORT_IMPL_H_
 #define ASH_CONTENT_SUPPORT_GPU_SUPPORT_IMPL_H_
 
+#include "ash/content_support/ash_with_content_export.h"
 #include "ash/gpu_support.h"
 
 namespace ash {
 
-class GPUSupportImpl : public GPUSupport {
+// Support for a real GPU, which relies on access to src/content.
+class ASH_WITH_CONTENT_EXPORT GPUSupportImpl : public GPUSupport {
  public:
   GPUSupportImpl();
   virtual ~GPUSupportImpl();
 
  private:
   // Overridden from GPUSupport:
   virtual bool IsPanelFittingDisabled() const OVERRIDE;
   virtual void DisableGpuWatchdog() OVERRIDE;
   virtual void GetGpuProcessHandles(
       const GetGpuProcessHandlesCallback& callback) const OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(GPUSupportImpl);
 };
 
 }  // namespace ash
 
 #endif  // ASH_CONTENT_SUPPORT_GPU_SUPPORT_IMPL_H_