Always destruct url request context getter on io thread....

chrome/browser/spellcheck_host.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 CHROME_BROWSER_SPELLCHECK_HOST_H_
 #define CHROME_BROWSER_SPELLCHECK_HOST_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 46 matching lines @@
   // The default place whether the spellcheck dictionary can reside is
   // chrome::DIR_APP_DICTIONARIES. However, for systemwide installations,
   // this directory may not have permissions for download. In that case, the
   // alternate directory for download is chrome::DIR_USER_DATA.
   void InitializeDictionaryLocation();
 
   // Load and parse the custom words dictionary and open the bdic file.
   // Executed on the file thread.
   void InitializeInternal();
 
+  void InitializeOnFileThread();
+
   // Inform |observer_| that initialization has finished.
   void InformObserverOfInitialization();
 
   // If |bdict_file_| is missing, we attempt to download it.
   void DownloadDictionary();
 
   // Write a custom dictionary addition to disk.
   void WriteWordToCustomDictionary(const std::string& word);
 
   // URLFetcher::Delegate implementation.  Called when we finish downloading the
   // spellcheck dictionary; saves the dictionary to |data_|.
   virtual void OnURLFetchComplete(const URLFetcher* source,
                                   const GURL& url,
                                   const URLRequestStatus& status,
                                   int response_code,
                                   const ResponseCookies& cookies,
                                   const std::string& data);
 
+  // Saves |data_| to disk. Run on the file thread.
+  void SaveDictionaryData();
+
   // May be NULL.
   Observer* observer_;
 
   // The desired location of the dictionary file (whether or not t exists yet).
   FilePath bdict_file_path_;
 
   // The location of the custom words file.
   FilePath custom_dictionary_file_;
 
   // The language of the dictionary file.
   std::string language_;
 
   // The file descriptor/handle for the dictionary file.
   base::PlatformFile file_;
 
   // In-memory cache of the custom words file.
   std::vector<std::string> custom_words_;
 
   // We don't want to attempt to download a missing dictionary file more than
   // once.
   bool tried_to_download_;
 
-  // Used for downloading the dictionary file.
-  scoped_refptr<URLRequestContextGetter> request_context_getter_;
+  // Data received from the dictionary download.
+  std::string data_;
+
+  // Used for downloading the dictionary file. We don't hold a reference, and
+  // it is only valid to use it on the UI thread.
+  URLRequestContextGetter* request_context_getter_;
 
   // Used for downloading the dictionary file.
   scoped_ptr<URLFetcher> fetcher_;
 };
 
 #endif  // CHROME_BROWSER_SPELLCHECK_HOST_H_