Fix sync test crashing when multiprofiles are enabled on Mac.

chrome/browser/profiles/profile_manager.cc

 // 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.
 
 #include <set>
 
 #include "chrome/browser/profiles/profile_manager.h"
 
 #include "base/command_line.h"
 #include "base/file_path.h"
@@ skipping 561 matching lines @@
 }
 
 // static
 bool ProfileManager::IsMultipleProfilesEnabled() {
   return CommandLine::ForCurrentProcess()->HasSwitch(switches::kMultiProfiles);
 }
 
 ProfileManagerWithoutInit::ProfileManagerWithoutInit(
     const FilePath& user_data_dir) : ProfileManager(user_data_dir) {
 }
+
+void ProfileManager::RegisterTestingProfile(Profile* profile,
+                                            bool add_to_cache) {
+  RegisterProfile(profile, true);
+  if (add_to_cache)
+    AddProfileToCache(profile);
+}