Mac Overlays: Add GPU back-pressure

content/common/gpu/gpu_messages.h

 // Copyright (c) 2012 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.
 
 // Multiply-included message file, hence no include guard here, but see below
 // for a much smaller-than-usual include guard section.
 
 #include <string>
 #include <vector>
 
@@ skipping 92 matching lines @@
 IPC_STRUCT_END()
 
 IPC_STRUCT_BEGIN(AcceleratedSurfaceMsg_BufferPresented_Params)
   // If the browser needs framerate throttling based on GPU back-pressure to be
   // disabled (e.g, because the NSView isn't visible but tab capture is active),
   // then this is set to true.
   IPC_STRUCT_MEMBER(bool, disable_throttling)
   // If the browser is drawing to the screen, this is the CGL renderer ID of
   // the GL context that the brower is using.
   IPC_STRUCT_MEMBER(int32, renderer_id)
+  // The CGDirectDisplayID on which the content was displayed, to be used for
+  // computing vsync. If vsync is not enabled, this is zero.
+  IPC_STRUCT_MEMBER(uint32, display_id_for_vsync)
 IPC_STRUCT_END()
 #endif
 
 IPC_STRUCT_BEGIN(AcceleratedJpegDecoderMsg_Decode_Params)
   IPC_STRUCT_MEMBER(int32, input_buffer_id)
   IPC_STRUCT_MEMBER(gfx::Size, coded_size)
   IPC_STRUCT_MEMBER(base::SharedMemoryHandle, input_buffer_handle)
   IPC_STRUCT_MEMBER(uint32, input_buffer_size)
   IPC_STRUCT_MEMBER(base::SharedMemoryHandle, output_video_frame_handle)
   IPC_STRUCT_MEMBER(uint32, output_buffer_size)
@@ skipping 673 matching lines @@
 IPC_MESSAGE_ROUTED0(AcceleratedJpegDecoderMsg_Destroy)
 
 //------------------------------------------------------------------------------
 // Accelerated JPEG Decoder Host Messages
 // These messages are sent from the GPU process to Browser process.
 //
 // Report decode status.
 IPC_MESSAGE_ROUTED2(AcceleratedJpegDecoderHostMsg_DecodeAck,
                     int32, /* bitstream_buffer_id */
                     media::JpegDecodeAccelerator::Error /* error */)