content: Pass IOSurface references using Mach IPC.

content/child/child_thread_impl.h

Index: content/child/child_thread_impl.h
diff --git a/content/child/child_thread_impl.h b/content/child/child_thread_impl.h
index b9efc4d2a5f8fd2532c98c5ffbdc1f4251e5d5c1..449aa2df58466a2ce742a5ed9916a70eff9e80d3 100644
--- a/content/child/child_thread_impl.h
+++ b/content/child/child_thread_impl.h
@@ -20,6 +20,10 @@
 #include "content/public/child/child_thread.h"
 #include "ipc/ipc_message.h"  // For IPC_MESSAGE_LOG_ENABLED.
 
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+#include "gpu/command_buffer/common/mailbox.h"
+#endif
+
 namespace base {
 class MessageLoop;
 
@@ -232,6 +236,9 @@ class CONTENT_EXPORT ChildThreadImpl
 #if defined(USE_TCMALLOC)
   void OnGetTcmallocStats();
 #endif
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+  void OnSetIOSurfaceManagerMailbox(const gpu::Mailbox& mailbox);
+#endif
 
   void EnsureConnected();