reland 31875. Revert was:...

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>
 
-#include "base/file_descriptor_posix.h"
 #include "base/file_path.h"
+#include "base/platform_file.h"
 #include "base/ref_counted.h"
 #include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/net/url_fetcher.h"
 #include "chrome/browser/net/url_request_context_getter.h"
 
 class SpellCheckHost : public base::RefCountedThreadSafe<SpellCheckHost,
                            ChromeThread::DeleteOnFileThread>,
                        public URLFetcher::Delegate {
  public:
   class Observer {
    public:
     virtual void SpellCheckHostInitialized() = 0;
   };
 
   SpellCheckHost(Observer* observer,
                  const std::string& language,
                  URLRequestContextGetter* request_context_getter);
 
   void Initialize();
 
   // Clear |observer_|. Used to prevent calling back to a deleted object.
   void UnsetObserver();
 
   // Add the given word to the custom words list and inform renderer of the
   // update.
   void AddWord(const std::string& word);
 
-  const base::FileDescriptor& bdict_fd() const { return fd_; };
+  const base::PlatformFile& bdict_file() const { return file_; }
 
   const std::vector<std::string>& custom_words() const { return custom_words_; }
 
   const std::string& last_added_word() const { return custom_words_.back(); }
 
   const std::string& language() const { return language_; }
 
  private:
   // These two classes can destruct us.
   friend class ChromeThread;
   friend class DeleteTask<SpellCheckHost>;
 
   virtual ~SpellCheckHost();
 
+  // Figure out the location for the dictionary. This is only non-trivial for
+  // Windows:
+  // 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();
 
   // 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 disk.
+  // 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);
 
   // May be NULL.
   Observer* observer_;
 
-  // The desired location of the dictionary file (whether or not it exists yet).
-  FilePath bdict_file_;
+  // 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_;
 
-  // On POSIX, the file descriptor for the dictionary file.
-  base::FileDescriptor fd_;
+  // 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_;
 
   // Used for downloading the dictionary file.
   scoped_ptr<URLFetcher> fetcher_;
 };
 
 #endif  // CHROME_BROWSER_SPELLCHECK_HOST_H_