Implement proxying for FileRef and FileChooser....

ppapi/c/private/ppb_proxy_private.h

Index: ppapi/c/private/ppb_proxy_private.h
===================================================================
--- ppapi/c/private/ppb_proxy_private.h	(revision 74966)
+++ ppapi/c/private/ppb_proxy_private.h	(working copy)
@@ -5,15 +5,20 @@
 #ifndef PPAPI_C_PRIVATE_PROXY_PRIVATE_H_
 #define PPAPI_C_PRIVATE_PROXY_PRIVATE_H_
 
+#include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_module.h"
+#include "ppapi/c/pp_resource.h"
 
-#define PPB_PROXY_PRIVATE_INTERFACE "PPB_Proxy_Private;1"
+#define PPB_PROXY_PRIVATE_INTERFACE "PPB_Proxy_Private;2"
 
 // Exposes functions needed by the out-of-process proxy to call into the
 // renderer PPAPI implementation.
 struct PPB_Proxy_Private {
   // Called when the given plugin process has crashed.
   void (*PluginCrashed)(PP_Module module);
+
+  // Returns the instance for the given resource, or 0 on failure.
+  PP_Instance (*GetInstanceForResource)(PP_Resource resource);
 };
 
 #endif  // PPAPI_C_PRIVATE_PROXY_PRIVATE_H_