Add detached mode plumbing

content/common/gpu_host_messages.h

 // Copyright 2016 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 "build/build_config.h"
 #include "content/common/content_export.h"
 #include "content/common/establish_channel_params.h"
@@ skipping 67 matching lines @@
   IPC_STRUCT_TRAITS_MEMBER(allow_view_command_buffers)
   IPC_STRUCT_TRAITS_MEMBER(allow_real_time_streams)
 IPC_STRUCT_TRAITS_END()
 
 #if defined(OS_MACOSX)
 IPC_STRUCT_TRAITS_BEGIN(content::AcceleratedSurfaceBuffersSwappedParams)
   IPC_STRUCT_TRAITS_MEMBER(surface_id)
   // Only one of ca_context_id or io_surface may be non-0.
   IPC_STRUCT_TRAITS_MEMBER(ca_context_id)
   IPC_STRUCT_TRAITS_MEMBER(io_surface)
+  IPC_STRUCT_TRAITS_MEMBER(use_detached)
+  IPC_STRUCT_TRAITS_MEMBER(detached_ca_context_id)
   IPC_STRUCT_TRAITS_MEMBER(size)
   IPC_STRUCT_TRAITS_MEMBER(scale_factor)
   IPC_STRUCT_TRAITS_MEMBER(latency_info)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(content::BufferPresentedParams)
   // The vsync parameters, to synchronize presentation with the display.
   IPC_STRUCT_TRAITS_MEMBER(surface_id)
   IPC_STRUCT_TRAITS_MEMBER(vsync_timebase)
   IPC_STRUCT_TRAITS_MEMBER(vsync_interval)
@@ skipping 192 matching lines @@
 // so the browser should stop sending the corresponding information
 IPC_MESSAGE_CONTROL2(GpuHostMsg_RemoveSubscription,
                      int32_t /* client_id */,
                      unsigned int /* target */)
 
 // Message from GPU to add a GPU log message to the about:gpu page.
 IPC_MESSAGE_CONTROL3(GpuHostMsg_OnLogMessage,
                      int /*severity*/,
                      std::string /* header */,
                      std::string /* message */)