Make DrawingBuffer and Canvas2DLayerBridge be cc::TextureLayerClients.

cc/blink/BUILD.gn

 # Copyright 2014 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.
 
 import("//testing/test.gni")
 
 # GYP version: //cc/blink/cc_blink.gyp:cc_blink
 component("blink") {
   output_name = "cc_blink"
 
   sources = [
     "cc_blink_export.h",
     "scrollbar_impl.cc",
     "scrollbar_impl.h",
     "web_compositor_support_impl.cc",
     "web_compositor_support_impl.h",
     "web_content_layer_impl.cc",
     "web_content_layer_impl.h",
     "web_display_item_list_impl.cc",
     "web_display_item_list_impl.h",
-    "web_external_bitmap_impl.cc",
-    "web_external_bitmap_impl.h",
     "web_external_texture_layer_impl.cc",
     "web_external_texture_layer_impl.h",
     "web_image_layer_impl.cc",
     "web_image_layer_impl.h",
     "web_layer_impl.cc",
     "web_layer_impl.h",
     "web_layer_impl_fixed_bounds.cc",
     "web_layer_impl_fixed_bounds.h",
     "web_scrollbar_layer_impl.cc",
     "web_scrollbar_layer_impl.h",
@@ skipping 33 matching lines @@
     "//cc",
     "//cc:test_support",
     "//skia",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/WebKit/public:blink",
     "//ui/gfx:test_support",
     "//ui/gfx/geometry",
   ]
 }