Implement proxying for FileRef and FileChooser....

ppapi/proxy/serialized_var.h

Index: ppapi/proxy/serialized_var.h
===================================================================
--- ppapi/proxy/serialized_var.h	(revision 74966)
+++ ppapi/proxy/serialized_var.h	(working copy)
@@ -215,6 +215,12 @@
 
   PP_Var Return(Dispatcher* dispatcher);
 
+  // Helper function for code that doesn't use the pattern above, but gets
+  // a return value from the remote side via a struct. You can pass in the
+  // SerializedVar and a PP_Var will be created with return value semantics.
+  static PP_Var Convert(Dispatcher* dispatcher,
+                        const SerializedVar& serialized);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ReceiveSerializedVarReturnValue);
 };
@@ -355,6 +361,11 @@
 
   void Return(Dispatcher* dispatcher, const PP_Var& var);
 
+  // Helper function for code that doesn't use the pattern above, but gets
+  // a return value from the remote side via a struct. You can pass in the
+  // SerializedVar and a PP_Var will be created with return value semantics.
+  static SerializedVar Convert(Dispatcher* dispatcher, const PP_Var& var);
+
  private:
   SerializedVar* serialized_;
 };