Thread ui opacity animations

cc/cc.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': {
     'cc_source_files': [
       'animation.cc',
       'animation.h',
       'animation_curve.cc',
       'animation_curve.h',
       'animation_events.h',
+      'animation_id_provider.cc',
+      'animation_id_provider.h',
       'animation_registrar.cc',
       'animation_registrar.h',
       'append_quads_data.h',
       'bitmap_content_layer_updater.cc',
       'bitmap_content_layer_updater.h',
       'bitmap_skpicture_content_layer_updater.cc',
       'bitmap_skpicture_content_layer_updater.h',
       'caching_bitmap_content_layer_updater.cc',
       'caching_bitmap_content_layer_updater.h',
       'checkerboard_draw_quad.cc',
@@ skipping 330 matching lines @@
         'include_dirs': [
           # TODO(jamesr): Remove once https://webkit.org/b/105259 lands + rolls
           '<(webkit_src_dir)/Source/Platform/chromium'
         ]
       },
       # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],
     },
   ],
 }