content: Pass IOSurface references using Mach IPC.

content/common/mac/io_surface_manager_token.h

Index: content/common/mac/io_surface_manager_token.h
diff --git a/content/common/mac/io_surface_manager_token.h b/content/common/mac/io_surface_manager_token.h
new file mode 100644
index 0000000000000000000000000000000000000000..cdaebf6568cf87eef0b981e032f573e8e6e38897
--- /dev/null
+++ b/content/common/mac/io_surface_manager_token.h
@@ -0,0 +1,16 @@
+// Copyright 2015 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.
+
+#ifndef CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_TOKEN_H_
+#define CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_TOKEN_H_

[Robert Sesek, 2015/05/28 18:25:11]

I'm not sure this needs its own file. Can it go in io_surface_manager.h or
io_surface_manager_messages.h ?

[reveman, 2015/05/29 00:09:02]

I prefer a separate file. io_surface_manager.h is meant for clients of the
IOSurfaceManager interface. The token doesn't belong in that file as it's an
implementation detail and not a requirement to implement that interface.

I could move it to io_surface_manager_messages.h but then files such as
render_process_host_impl.h and child_process_messages.h which only care about
the token would have to include that file even though the definition of Mach
messages is not something the code in those files should be aware of.

+
+#include "gpu/command_buffer/common/mailbox.h"
+
+namespace content {
+
+using IOSurfaceManagerToken = gpu::Mailbox;
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_MAC_IO_SURFACE_MANAGER_TOKEN_H_