Add fallback behavior if the last used profile cannot initialize

chrome/browser/profiles/profiles_state.h

 // Copyright 2013 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_PROFILES_PROFILES_STATE_H_
 #define CHROME_BROWSER_PROFILES_PROFILES_STATE_H_
 
+#include <string>
 #include <vector>
 #include "base/strings/string16.h"
 #include "chrome/browser/profiles/avatar_menu.h"
 
 class Browser;
 class PrefRegistrySimple;
 class Profile;
 class SigninErrorController;
 namespace base { class FilePath; }
 
@@ skipping 84 matching lines @@
 // Sets the last used profile pref to |profile_dir|, unless |profile_dir| is the
 // System Profile directory, which is an invalid last used profile.
 void SetLastUsedProfile(const std::string& profile_dir);
 
 // Returns true if all non-supervised and non-child profiles are locked.
 bool AreAllProfilesLocked();
 
 }  // namespace profiles
 
 #endif  // CHROME_BROWSER_PROFILES_PROFILES_STATE_H_