Add flow control between renderer and GPU processes, and, on Mac OS X,...

gpu/command_buffer/service/gpu_processor_mac.cc

 // Copyright (c) 2010 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 "app/gfx/gl/gl_context.h"
 #include "gpu/command_buffer/service/gpu_processor.h"
 
 using ::base::SharedMemory;
 
 namespace gpu {
@@ skipping 81 matching lines @@
       Callback1<TransportDIB::Id>::Type* deallocator) {
   surface_->SetTransportDIBAllocAndFree(allocator, deallocator);
 }
 
 uint64 GPUProcessor::GetSurfaceId() {
   if (!surface_.get())
     return 0;
   return surface_->GetSurfaceId();
 }
 
+uint64 GPUProcessor::swap_buffers_count() const {
+  return swap_buffers_count_;
+}
+
+void GPUProcessor::set_acknowledged_swap_buffers_count(
+    uint64 acknowledged_swap_buffers_count) {
+  acknowledged_swap_buffers_count_ = acknowledged_swap_buffers_count;
+}
+
 void GPUProcessor::WillSwapBuffers() {
   DCHECK(decoder_.get());
   DCHECK(decoder_->GetGLContext());
   DCHECK(decoder_->GetGLContext()->IsCurrent());
 
+  ++swap_buffers_count_;
+
   if (surface_.get()) {
     surface_->SwapBuffers();
   }
 
   if (wrapped_swap_buffers_callback_.get()) {
     wrapped_swap_buffers_callback_->Run();
   }
 }
 
 }  // namespace gpu