Revert 186627

content/browser/browser_plugin/browser_plugin_guest.h

Index: content/browser/browser_plugin/browser_plugin_guest.h
===================================================================
--- content/browser/browser_plugin/browser_plugin_guest.h	(revision 186756)
+++ content/browser/browser_plugin/browser_plugin_guest.h	(working copy)
@@ -50,10 +50,6 @@
 class WebCursor;
 struct WebDropData;
 
-namespace gpu {
-struct Mailbox;
-}
-
 namespace WebKit {
 class WebInputEvent;
 }
@@ -185,7 +181,7 @@
   // BrowserPluginGuest is already destroyed.
   static void AcknowledgeBufferPresent(int route_id,
                                        int gpu_host_id,
-                                       const gpu::Mailbox& mailbox_name,
+                                       const std::string& mailbox_name,
                                        uint32 sync_point);
 
   // Returns whether BrowserPluginGuest is interested in receiving the given
@@ -296,7 +292,7 @@
   void OnSwapBuffersACK(int instance_id,
                         int route_id,
                         int gpu_host_id,
-                        const gpu::Mailbox& mailbox_name,
+                        const std::string& mailbox_name,
                         uint32 sync_point);
 
   void OnTerminateGuest(int instance_id);