Add a Material Design Circular Activity Indicator (Spinner) view for Mac.

chrome/chrome_browser_ui.gypi

 # Copyright 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': {
     # There are two sections of sources:
     # * "Platform"-based sources (OS, toolkit, etc.)
     # * Feature/directory-based sources (e.g., history, printing)
 
@@ skipping 554 matching lines @@
       'browser/ui/cocoa/location_bar/selected_keyword_decoration.mm',
       'browser/ui/cocoa/location_bar/star_decoration.h',
       'browser/ui/cocoa/location_bar/star_decoration.mm',
       'browser/ui/cocoa/location_bar/translate_decoration.h',
       'browser/ui/cocoa/location_bar/translate_decoration.mm',
       'browser/ui/cocoa/location_bar/zoom_decoration.h',
       'browser/ui/cocoa/location_bar/zoom_decoration.mm',
       'browser/ui/cocoa/login_prompt_cocoa.h',
       'browser/ui/cocoa/login_prompt_cocoa.mm',
       'browser/ui/cocoa/main_menu_item.h',
+      'browser/ui/cocoa/circular_activity_indicator_view.h',
+      'browser/ui/cocoa/circular_activity_indicator_view.mm',
       'browser/ui/cocoa/media_picker/desktop_media_picker_bridge.h',
       'browser/ui/cocoa/media_picker/desktop_media_picker_bridge.mm',
       'browser/ui/cocoa/media_picker/desktop_media_picker_cocoa.h',
       'browser/ui/cocoa/media_picker/desktop_media_picker_cocoa.mm',
       'browser/ui/cocoa/media_picker/desktop_media_picker_controller.h',
       'browser/ui/cocoa/media_picker/desktop_media_picker_controller.mm',
       'browser/ui/cocoa/media_picker/desktop_media_picker_item.h',
       'browser/ui/cocoa/media_picker/desktop_media_picker_item.mm',
       'browser/ui/cocoa/menu_button.h',
       'browser/ui/cocoa/menu_button.mm',
@@ skipping 2600 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }