[PPAPI] Added a new Var subclass, ResourceVar.

ppapi/shared_impl/var.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ppapi/shared_impl/var.h"
 
 #include <limits>
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 73 matching lines @@
 }
 
 ArrayVar* Var::AsArrayVar() {
   return NULL;
 }
 
 DictionaryVar* Var::AsDictionaryVar() {
   return NULL;
 }
 
+ResourceVar* Var::AsResourceVar() {
+  return NULL;
+}
+
 PP_Var Var::GetPPVar() {
   int32 id = GetOrCreateVarID();
   if (!id)
     return PP_MakeNull();
 
   PP_Var result;
   result.type = GetType();
   result.padding = 0;
   result.value.as_id = id;
   return result;
@@ skipping 98 matching lines @@
     return NULL;
   scoped_refptr<Var> var_object(
       PpapiGlobals::Get()->GetVarTracker()->GetVar(var));
   if (!var_object.get())
     return NULL;
   return var_object->AsArrayBufferVar();
 }
 
 }  // namespace ppapi