[Mac] Flip the flag for multi-profiles to on by default.

chrome/chrome_tests.gypi

 # 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.
 
 {
   'variables' : {
     'pyautolib_sources': [
       'app/chrome_command_ids.h',
       'app/chrome_dll_resource.h',
       'common/automation_constants.h',
@@ skipping 164 matching lines @@
         'test/base/test_tab_strip_model_observer.h',
         'test/base/test_url_request_context_getter.cc',
         'test/base/test_url_request_context_getter.h',
         'test/base/testing_browser_process.cc',
         'test/base/testing_browser_process.h',
         'test/base/testing_browser_process_test.h',
         'test/base/testing_pref_service.cc',
         'test/base/testing_pref_service.h',
         'test/base/testing_profile.cc',
         'test/base/testing_profile.h',
+        'test/base/testing_profile_manager.cc',
+        'test/base/testing_profile_manager.h',
         'test/base/thread_observer_helper.h',
         'test/base/ui_test_utils.cc',
         'test/base/ui_test_utils.h',
         'test/base/ui_test_utils_linux.cc',
         'test/base/ui_test_utils_mac.mm',
         'test/base/ui_test_utils_win.cc',
         'test/base/values_test_util.cc',
         'test/base/values_test_util.h',
         'test/test_navigation_observer.cc',
         'test/test_navigation_observer.h',
@@ skipping 3944 matching lines @@
               # Use outputs of this action as inputs for the main target build.
               # Seems as a misnomer but makes this happy on Linux (scons).
               'process_outputs_as_sources': 1,
             },
           ],  # 'actions'
         },
       ]
     }],  # 'coverage!=0'
   ],  # 'conditions'
 }