Added support for multiple parameters to Extension API callbacks.

chrome/browser/extensions/extension_debugger_api.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.
 
 // Implements the Chrome Extensions Debugger API.
 
 #include "chrome/browser/extensions/extension_debugger_api.h"
 
 #include <map>
 #include <set>
@@ skipping 467 matching lines @@
     DictionaryValue* dictionary) {
   Value* error_body;
   if (dictionary->Get("error", &error_body)) {
     base::JSONWriter::Write(error_body, &error_);
     SendResponse(false);
     return;
   }
 
   Value* result_body;
   if (dictionary->Get("result", &result_body))
-    result_.reset(result_body->DeepCopy());
+    SetSingleResult(result_body->DeepCopy());
   else
-    result_.reset(new DictionaryValue());
+    SetSingleResult(new DictionaryValue());
   SendResponse(true);
 }