Return first_run_win to using the Chrome path provider to look up the user data dir.

chrome/browser/first_run/first_run_internal.h

 // 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.
 
 #ifndef CHROME_BROWSER_FIRST_RUN_FIRST_RUN_INTERNAL_H_
 #define CHROME_BROWSER_FIRST_RUN_FIRST_RUN_INTERNAL_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 20 matching lines @@
 
 enum FirstRunState {
   FIRST_RUN_UNKNOWN,  // The state is not tested or set yet.
   FIRST_RUN_TRUE,
   FIRST_RUN_FALSE
 };
 
 // This variable should only be accessed through IsChromeFirstRun().
 extern FirstRunState first_run_;
 
-// The kSentinelFile file absence will tell us it is a first run.
-extern const char* const kSentinelFile;
-
 // Loads master preferences from the master preference file into the installer
 // master preferences. Passes the master preference file path out in
 // master_prefs_path. Returns the pointer to installer::MasterPreferences object
 // if successful; otherwise, returns NULL.
 installer::MasterPreferences* LoadMasterPrefs(FilePath* master_prefs_path);
 
 // Copies user preference file to master preference file. Returns true if
 // successful.
 bool CopyPrefFile(const FilePath& user_data_dir,
                   const FilePath& master_prefs_path);
@@ skipping 58 matching lines @@
                                    const CommandLine& cmdline);
 
 #if !defined(OS_WIN)
 bool ImportBookmarks(const FilePath& import_bookmarks_path);
 #endif
 
 }  // namespace internal
 }  // namespace first_run
 
 #endif  // CHROME_BROWSER_FIRST_RUN_FIRST_RUN_INTERNAL_H_