cc: Create a LayerScrollClient interface and an adapter class in compositor_bindings.

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': {
     'chromium_code': 1,
     'cc_source_files': [
       'animation/animation.cc',
       'animation/animation.h',
@@ skipping 90 matching lines @@
       'layers/io_surface_layer_impl.h',
       'layers/layer.cc',
       'layers/layer.h',
       'layers/layer_impl.cc',
       'layers/layer_impl.h',
       'layers/layer_iterator.cc',
       'layers/layer_iterator.h',
       'layers/layer_lists.h',
       'layers/layer_position_constraint.cc',
       'layers/layer_position_constraint.h',
+      'layers/layer_scroll_client.h',
       'layers/nine_patch_layer.cc',
       'layers/nine_patch_layer.h',
       'layers/nine_patch_layer_impl.cc',
       'layers/nine_patch_layer_impl.h',
       'layers/paint_properties.h',
       'layers/picture_image_layer.cc',
       'layers/picture_image_layer.h',
       'layers/picture_image_layer_impl.cc',
       'layers/picture_image_layer_impl.h',
       'layers/picture_layer.cc',
@@ skipping 252 matching lines @@
         'CC_IMPLEMENTATION=1',
       ],
       'sources': [
         '<@(cc_source_files)',
       ],
       # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],
     },
   ],
 }