Use WeakPtr for posting cc tasks to main thread

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': [
       'active_animation.cc',
       'active_animation.h',
       'animation_curve.cc',
@@ skipping 190 matching lines @@
       'resource_update_queue.h',
       'scheduler.cc',
       'scheduler.h',
       'scheduler_state_machine.cc',
       'scheduler_state_machine.h',
       'scoped_ptr_deque.h',
       'scoped_ptr_hash_map.h',
       'scoped_ptr_vector.h',
       'scoped_resource.cc',
       'scoped_resource.h',
-      'scoped_thread_proxy.cc',
-      'scoped_thread_proxy.h',
       'scrollbar_animation_controller.cc',
       'scrollbar_animation_controller.h',
       'scrollbar_animation_controller_linear_fade.cc',
       'scrollbar_animation_controller_linear_fade.h',
       'scrollbar_geometry_fixed_thumb.cc',
       'scrollbar_geometry_fixed_thumb.h',
       'scrollbar_geometry_stub.cc',
       'scrollbar_geometry_stub.h',
       'scrollbar_layer.cc',
       'scrollbar_layer.h',
@@ skipping 102 matching lines @@
       ],
       'all_dependent_settings': {
         'include_dirs': [
           # TODO(jamesr): Remove once https://webkit.org/b/105259 lands + rolls
           '<(webkit_src_dir)/Source/Platform/chromium'
         ]
       }
     },
   ],
 }