Delay the response to ChildProcessHostMsg_SyncAllocateGpuMemoryBuffer via a callback to allow for b…

content/common/gpu/client/gpu_memory_buffer_impl_shm.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_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_SHM_H_
 #define CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_SHM_H_
 
 #include "content/common/gpu/client/gpu_memory_buffer_impl.h"
 
 namespace content {
 
 // Implementation of GPU memory buffer based on shared memory.
 class GpuMemoryBufferImplShm : public GpuMemoryBufferImpl {
  public:
   GpuMemoryBufferImplShm(const gfx::Size& size, unsigned internalformat);
   virtual ~GpuMemoryBufferImplShm();
 
   // Allocates a shared memory backed GPU memory buffer with |size| and
   // |internalformat| for use by |child_process|.
   static void AllocateSharedMemoryForChildProcess(
       const gfx::Size& size,
       unsigned internalformat,
       base::ProcessHandle child_process,
-      gfx::GpuMemoryBufferHandle* handle);
+      const AllocationCallback& callback);
 
   static bool IsLayoutSupported(const gfx::Size& size, unsigned internalformat);
   static bool IsUsageSupported(unsigned usage);
   static bool IsConfigurationSupported(const gfx::Size& size,
                                        unsigned internalformat,
                                        unsigned usage);
 
   bool Initialize();
   bool InitializeFromHandle(gfx::GpuMemoryBufferHandle handle);
 
   // Overridden from gfx::GpuMemoryBuffer:
   virtual void* Map() OVERRIDE;
   virtual void Unmap() OVERRIDE;
   virtual uint32 GetStride() const OVERRIDE;
   virtual gfx::GpuMemoryBufferHandle GetHandle() const OVERRIDE;
 
  private:
   scoped_ptr<base::SharedMemory> shared_memory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuMemoryBufferImplShm);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_SHM_H_