Reduce the copying of string data between C++ and javascript in proxy_resolver_v8.cc.

net/proxy/init_proxy_resolver.h

 // Copyright (c) 2009 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.
 
 #ifndef NET_PROXY_INIT_PROXY_RESOLVER_H_
 #define NET_PROXY_INIT_PROXY_RESOLVER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 79 matching lines @@
 
   ProxyResolver* resolver_;
   ProxyScriptFetcher* proxy_script_fetcher_;
 
   CompletionCallbackImpl<InitProxyResolver> io_callback_;
   CompletionCallback* user_callback_;
 
   size_t current_pac_url_index_;
 
   // Filled when the PAC script fetch completes.
-  std::string pac_bytes_;
+  string16 pac_script_;
 
   UrlList pac_urls_;
   State next_state_;
 
   BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(InitProxyResolver);
 };
 
 }  // namespace net
 
 #endif  // NET_PROXY_INIT_PROXY_RESOLVER_H_