Make painting app list items more efficient by caching the labels.

ui/app_list/app_list.gyp

 # 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 49 matching lines @@
         'views/app_list_background.cc',
         'views/app_list_background.h',
         'views/app_list_item_view.cc',
         'views/app_list_item_view.h',
         'views/app_list_main_view.cc',
         'views/app_list_main_view.h',
         'views/app_list_view.cc',
         'views/app_list_view.h',
         'views/apps_grid_view.cc',
         'views/apps_grid_view.h',
+        'views/cached_label.cc',
+        'views/cached_label.h',
         'views/contents_view.cc',
         'views/contents_view.h',
         'views/page_switcher.cc',
         'views/page_switcher.h',
         'views/pulsing_block_view.cc',
         'views/pulsing_block_view.h',
         'views/search_box_view.cc',
         'views/search_box_view.h',
         'views/search_result_list_view.cc',
         'views/search_result_list_view.h',
@@ skipping 85 matching lines @@
           'sources/': [
             ['exclude', 'cocoa/'],
           ],
         }],
       ],
       # Disable c4267 warnings until we fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],
     },
   ],
 }