Implement Desktop Media Picker (Mac version) for Desktop Capture API

chrome/chrome_tests_unit.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.
 {
   'targets': [
     {
       # This target contains mocks and test utilities that don't belong in
       # production libraries but are used by more than one test executable.
       'target_name': 'test_support_common',
       'type': 'static_library',
@@ skipping 1500 matching lines @@
         'browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.h',
         'browser/ui/cocoa/infobars/translate_infobar_unittest.mm',
         'browser/ui/cocoa/location_bar/autocomplete_text_field_cell_unittest.mm',
         'browser/ui/cocoa/location_bar/autocomplete_text_field_editor_unittest.mm',
         'browser/ui/cocoa/location_bar/autocomplete_text_field_unittest.mm',
         'browser/ui/cocoa/location_bar/autocomplete_text_field_unittest_helper.mm',
         'browser/ui/cocoa/location_bar/ev_bubble_decoration_unittest.mm',
         'browser/ui/cocoa/location_bar/image_decoration_unittest.mm',
         'browser/ui/cocoa/location_bar/keyword_hint_decoration_unittest.mm',
         'browser/ui/cocoa/location_bar/selected_keyword_decoration_unittest.mm',
+        'browser/ui/cocoa/media_picker/desktop_media_picker_controller_unittest.mm',
         'browser/ui/cocoa/menu_button_unittest.mm',
         'browser/ui/cocoa/nine_part_button_cell_unittest.mm',
         'browser/ui/cocoa/notifications/balloon_controller_unittest.mm',
         'browser/ui/cocoa/notifications/message_center_tray_bridge_unittest.mm',
         'browser/ui/cocoa/nsmenuitem_additions_unittest.mm',
         'browser/ui/cocoa/nsview_additions_unittest.mm',
         'browser/ui/cocoa/omnibox/omnibox_popup_cell_unittest.mm',
         'browser/ui/cocoa/omnibox/omnibox_popup_matrix_unittest.mm',
         'browser/ui/cocoa/omnibox/omnibox_popup_separator_view_unittest.mm',
         'browser/ui/cocoa/omnibox/omnibox_popup_view_mac_unittest.mm',
@@ skipping 1229 matching lines @@
               # more details.
               'DebugInformationFormat': '3',
               'ProgramDataBaseFileName': '<(PRODUCT_DIR)/unit_tests.exe.pdb',
             },
           },
         },
       ],
     }],
   ],  # 'conditions'
 }