views: Add optional overlay image to ImageButton

ui/views/views.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,
   },
 
   'target_defaults': {
     'conditions': [
@@ skipping 449 matching lines @@
         'views',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
         'accessible_pane_view_unittest.cc',
         'animation/bounds_animator_unittest.cc',
         'bubble/bubble_delegate_unittest.cc',
         'bubble/bubble_frame_view_unittest.cc',
+        'controls/button/image_button_unittest.cc',
         'controls/combobox/native_combobox_views_unittest.cc',
         'controls/label_unittest.cc',
         'controls/menu/menu_model_adapter_unittest.cc',
         'controls/progress_bar_unittest.cc',
         'controls/scrollbar/scrollbar_unittest.cc',
         'controls/single_split_view_unittest.cc',
         'controls/slider_unittest.cc',
         'controls/tabbed_pane/tabbed_pane_unittest.cc',
         'controls/table/table_view_unittest.cc',
         'controls/textfield/native_textfield_views_unittest.cc',
@@ skipping 208 matching lines @@
         ['use_aura==1', {
           'dependencies': [
             '../gfx/compositor/compositor.gyp:compositor',
             '../gfx/compositor/compositor.gyp:compositor_test_support',
           ],
         }],
       ],
     },  # target_name: views_examples_lib
   ],
 }