Fix flaky linux panel tests related to active state checks

chrome/chrome_tests.gypi

 # 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.
 {
   'variables' : {
     'pyautolib_sources': [
       'app/chrome_command_ids.h',
       'app/chrome_dll_resource.h',
       'common/automation_constants.h',
       'common/pref_names.cc',
@@ skipping 155 matching lines @@
         'browser/ssl/ssl_client_auth_requestor_mock.h',
         'browser/ui/browser.h',
         'browser/ui/cocoa/run_loop_testing.h',
         'browser/ui/cocoa/run_loop_testing.mm',
         'browser/ui/fullscreen/fullscreen_controller_test.cc',
         'browser/ui/fullscreen/fullscreen_controller_test.h',
         'browser/ui/panels/base_panel_browser_test.cc',
         'browser/ui/panels/base_panel_browser_test.h',
         'browser/ui/panels/old_base_panel_browser_test.cc',
         'browser/ui/panels/old_base_panel_browser_test.h',
+        'browser/ui/panels/test_panel_active_state_observer.cc',
+        'browser/ui/panels/test_panel_active_state_observer.h',
         'browser/ui/panels/test_panel_mouse_watcher.cc',
         'browser/ui/panels/test_panel_mouse_watcher.h',
         'browser/ui/tab_contents/test_tab_contents.cc',
         'browser/ui/tab_contents/test_tab_contents.h',
         'common/extensions/extension_builder.cc',
         'common/extensions/extension_builder.h',
         'common/extensions/value_builder.cc',
         'common/extensions/value_builder.h',
         'common/net/gaia/mock_url_fetcher_factory.h',
         'common/pref_store_observer_mock.cc',
@@ skipping 4482 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'
 }