[Mac] Create CrTrackingArea and use it in TabStripController.

chrome/chrome_browser.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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': '<(library)',
       'msvs_guid': '5BF908A7-68FB-4A4B-99E3-8C749F1FE4EA',
@@ skipping 2817 matching lines @@
         'browser/ui/cocoa/themed_window.h',
         'browser/ui/cocoa/themed_window.mm',
         'browser/ui/cocoa/toolbar/back_forward_menu_controller.h',
         'browser/ui/cocoa/toolbar/back_forward_menu_controller.mm',
         'browser/ui/cocoa/toolbar/reload_button.h',
         'browser/ui/cocoa/toolbar/reload_button.mm',
         'browser/ui/cocoa/toolbar/toolbar_controller.h',
         'browser/ui/cocoa/toolbar/toolbar_controller.mm',
         'browser/ui/cocoa/toolbar/toolbar_view.h',
         'browser/ui/cocoa/toolbar/toolbar_view.mm',
+        'browser/ui/cocoa/tracking_area.h',
+        'browser/ui/cocoa/tracking_area.mm',
         'browser/ui/cocoa/translate/after_translate_infobar_controller.h',
         'browser/ui/cocoa/translate/after_translate_infobar_controller.mm',
         'browser/ui/cocoa/translate/before_translate_infobar_controller.h',
         'browser/ui/cocoa/translate/before_translate_infobar_controller.mm',
         'browser/ui/cocoa/translate/translate_infobar_base.h',
         'browser/ui/cocoa/translate/translate_infobar_base.mm',
         'browser/ui/cocoa/translate/translate_message_infobar_controller.h',
         'browser/ui/cocoa/translate/translate_message_infobar_controller.mm',
         'browser/ui/cocoa/ui_localizer.h',
         'browser/ui/cocoa/ui_localizer.mm',
@@ skipping 1756 matching lines @@
       ],
     },
   ],
 }
 
 # Local Variables:
 # tab-width:2
 # indent-tabs-mode:nil
 # End:
 # vim: set expandtab tabstop=2 shiftwidth=2: