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

content/common/gpu/client/gpu_memory_buffer_impl_win.cc

 // 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.
 
 #include "content/common/gpu/client/gpu_memory_buffer_impl.h"
 
 #include "content/common/gpu/client/gpu_memory_buffer_impl_shm.h"
 
 namespace content {
 
@@ skipping 14 matching lines @@
 
   return scoped_ptr<GpuMemoryBufferImpl>();
 }
 
 // static
 void GpuMemoryBufferImpl::AllocateForChildProcess(
     const gfx::Size& size,
     unsigned internalformat,
     unsigned usage,
     base::ProcessHandle child_process,
-    gfx::GpuMemoryBufferHandle* handle) {
+    const AllocationCallback& callback) {
+  handle->type = gfx::EMPTY_BUFFER;

[reveman, 2014/05/19 18:57:57]

nit: think you forgot to remove this line

   if (GpuMemoryBufferImplShm::IsConfigurationSupported(
           size, internalformat, usage)) {
     GpuMemoryBufferImplShm::AllocateSharedMemoryForChildProcess(
-        size, internalformat, child_process, handle);
+        size, internalformat, child_process, callback);
     return;
   }
 
-  handle->type = gfx::EMPTY_BUFFER;
+  callback.Run(gfx::GpuMemoryBufferHandle());
 }
 
 // static
 scoped_ptr<GpuMemoryBufferImpl> GpuMemoryBufferImpl::CreateFromHandle(
     gfx::GpuMemoryBufferHandle handle,
     const gfx::Size& size,
     unsigned internalformat) {
   switch (handle.type) {
     case gfx::SHARED_MEMORY_BUFFER: {
       scoped_ptr<GpuMemoryBufferImplShm> buffer(
           new GpuMemoryBufferImplShm(size, internalformat));
       if (!buffer->InitializeFromHandle(handle))
         return scoped_ptr<GpuMemoryBufferImpl>();
 
       return buffer.PassAs<GpuMemoryBufferImpl>();
     }
     default:
       return scoped_ptr<GpuMemoryBufferImpl>();
   }
 }
 
 }  // namespace content