gpu: InProcessCommandBuffer::DestroyTransferBuffer thread safe

gpu/command_buffer/service/in_process_command_buffer.cc

Index: gpu/command_buffer/service/in_process_command_buffer.cc
diff --git a/gpu/command_buffer/service/in_process_command_buffer.cc b/gpu/command_buffer/service/in_process_command_buffer.cc
index 0411806916805c306e093b0b6d38f840c067cf31..2fb59f9a817c09ecfd3084e1449efccf72977cec 100644
--- a/gpu/command_buffer/service/in_process_command_buffer.cc
+++ b/gpu/command_buffer/service/in_process_command_buffer.cc
@@ -591,13 +591,19 @@ scoped_refptr<Buffer> InProcessCommandBuffer::CreateTransferBuffer(size_t size,
 
 void InProcessCommandBuffer::DestroyTransferBuffer(int32 id) {
   CheckSequencedThread();
-  base::Closure task = base::Bind(&CommandBuffer::DestroyTransferBuffer,
-                                  base::Unretained(command_buffer_.get()),
-                                  id);
+  base::Closure task =
+      base::Bind(&InProcessCommandBuffer::DestroyTransferBufferOnGputhread,
+                 base::Unretained(this),
+                 id);
 
   QueueTask(task);
 }
 
+void InProcessCommandBuffer::DestroyTransferBufferOnGputhread(int32 id) {
+  base::AutoLock lock(command_buffer_lock_);
+  command_buffer_->DestroyTransferBuffer(id);
+}
+
 gpu::Capabilities InProcessCommandBuffer::GetCapabilities() {
   return capabilities_;
 }