Implement open_resource in non-SFI mode.

ppapi/proxy/ppapi_messages.h

Index: ppapi/proxy/ppapi_messages.h
diff --git a/ppapi/proxy/ppapi_messages.h b/ppapi/proxy/ppapi_messages.h
index 10cde4e4e435f3d66d230ed191ef4354b4f5a3b5..5fe5e9684edf7c1d340d779de17cac2de50b1fab 100644
--- a/ppapi/proxy/ppapi_messages.h
+++ b/ppapi/proxy/ppapi_messages.h
@@ -756,6 +756,11 @@ IPC_MESSAGE_CONTROL1(PpapiHostMsg_ChannelCreated,
 // Notify the renderer that the PPAPI channel gets ready in the plugin.
 IPC_MESSAGE_CONTROL0(PpapiHostMsg_StartupInitializationComplete);
 
+// Calls renderer to open a resource file for nacl_irt_open_resource().
+IPC_SYNC_MESSAGE_CONTROL1_1(PpapiHostMsg_OpenResource,
+                            std::string /* key */,
+                            ppapi::proxy::SerializedHandle /* fd */)
+
 // Logs the given message to the console of all instances.
 IPC_MESSAGE_CONTROL4(PpapiHostMsg_LogWithSource,
                      PP_Instance /* instance */,