Refactor Pickle Read methods to use higher performance PickleIterator.

chrome/browser/extensions/execute_code_in_tab_function.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 "chrome/browser/extensions/execute_code_in_tab_function.h"
 
 #include "base/bind.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 220 matching lines @@
   Observe(contents->web_contents());
   AddRef();  // balanced in OnExecuteCodeFinished()
   return true;
 }
 
 bool ExecuteCodeInTabFunction::OnMessageReceived(const IPC::Message& message) {
   if (message.type() != ExtensionHostMsg_ExecuteCodeFinished::ID)
     return false;
 
   int message_request_id;
-  void* iter = NULL;
+  PickleIterator iter(message);
   if (!message.ReadInt(&iter, &message_request_id)) {
     NOTREACHED() << "malformed extension message";
     return true;
   }
 
   if (message_request_id != request_id())
     return false;
 
   IPC_BEGIN_MESSAGE_MAP(ExecuteCodeInTabFunction, message)
     IPC_MESSAGE_HANDLER(ExtensionHostMsg_ExecuteCodeFinished,
                         OnExecuteCodeFinished)
   IPC_END_MESSAGE_MAP()
   return true;
 }
 
 void ExecuteCodeInTabFunction::OnExecuteCodeFinished(int request_id,
                                                      bool success,
                                                      const std::string& error) {
   if (!error.empty()) {
     CHECK(!success);
     error_ = error;
   }
 
   SendResponse(success);
 
   Observe(NULL);
   Release();  // balanced in Execute()
 }