Remove the assumption about client_id from gpu memory buffer allocation on the browser side.

content/common/gpu/client/gpu_memory_buffer_impl.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_H_
 #define CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_H_
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/gfx/gpu_memory_buffer.h"
 #include "ui/gfx/size.h"
 
 namespace content {
 
 // Provides common implementation of a GPU memory buffer.
 class GpuMemoryBufferImpl : public gfx::GpuMemoryBuffer {
  public:
   typedef base::Callback<void(scoped_ptr<GpuMemoryBufferImpl> buffer)>
       CreationCallback;
   typedef base::Callback<void(const gfx::GpuMemoryBufferHandle& handle)>
       AllocationCallback;
 
   virtual ~GpuMemoryBufferImpl();
 
   // Creates a GPU memory buffer instance with |size| and |internalformat| for
   // |usage|.

[reveman, 2014/09/10 16:10:14]

Please update this comment. Something along the lines of. "for |usage| by
current process and |client_id|"

   static void Create(const gfx::Size& size,
                      unsigned internalformat,
                      unsigned usage,
+                     int gpu_client_id,

[reveman, 2014/09/10 16:10:13]

Sorry, I'd prefer "client_id" rather than gpu_client_id here and in all
GpuMemoryBuffer related classes as this code should not really be aware of a GPU
"process". This is just some opaque client ID as for as this code cares.

                      const CreationCallback& callback);
 
   // Allocates a GPU memory buffer with |size| and |internalformat| for |usage|
   // by |child_process| identified by |child_id|. The |handle| returned can be

[reveman, 2014/09/10 16:10:14]

I think we should change "for |usage| by |child_process| identified by
|child_id|" to "for |usage| by |child_process| and |child_client_id|" and not
make the assumption that there's one client_id per child process.

   // used by the |child_process| to create an instance of this class.
   static void AllocateForChildProcess(const gfx::Size& size,
                                       unsigned internalformat,
                                       unsigned usage,
                                       base::ProcessHandle child_process,
                                       int child_id,

[reveman, 2014/09/10 16:10:14]

Please s/child_id/child_client_id/ to make the connection between this and
client_id above clear.

                                       const AllocationCallback& callback);
 
   // Notify that GPU memory buffer has been deleted by |child_process|.
   static void DeletedByChildProcess(gfx::GpuMemoryBufferType type,
                                     const gfx::GpuMemoryBufferId& id,
                                     base::ProcessHandle child_process);
 
   // Creates an instance from the given |handle|. |size| and |internalformat|
   // should match what was used to allocate the |handle|.
   static scoped_ptr<GpuMemoryBufferImpl> CreateFromHandle(
@@ skipping 20 matching lines @@
   const gfx::Size size_;
   const unsigned internalformat_;
   bool mapped_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuMemoryBufferImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_GPU_MEMORY_BUFFER_IMPL_H_