Fix race condition in utility process clients

chrome/browser/extensions/webstore_install_helper.h

 // Copyright (c) 2011 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 CHROME_BROWSER_EXTENSIONS_WEBSTORE_INSTALL_HELPER_H_
 #define CHROME_BROWSER_EXTENSIONS_WEBSTORE_INSTALL_HELPER_H_
 #pragma once
 
 #include "content/browser/utility_process_host.h"
 #include "content/public/common/url_fetcher_delegate.h"
@@ skipping 86 matching lines @@
   // |icon_url_| is non-empty, it needs to be fetched and decoded into an
   // SkBitmap.
   std::string icon_base64_data_;
   GURL icon_url_;
   std::vector<unsigned char> fetched_icon_data_;
 
   // For fetching the icon, if needed.
   scoped_ptr<content::URLFetcher> url_fetcher_;
   net::URLRequestContextGetter* context_getter_; // Only usable on UI thread.
 
-  UtilityProcessHost* utility_host_;
+  base::WeakPtr<UtilityProcessHost> utility_host_;
 
   // Flags for whether we're done doing icon decoding and manifest parsing.
   bool icon_decode_complete_;
   bool manifest_parse_complete_;
 
   // The results of succesful decoding/parsing.
   SkBitmap icon_;
   scoped_ptr<base::DictionaryValue> parsed_manifest_;
 
   // A details string for keeping track of any errors.
   std::string error_;
 
   // A code to distinguish between an error with the icon, and an error with the
   // manifest.
   Delegate::InstallHelperResultCode parse_error_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_WEBSTORE_INSTALL_HELPER_H_