cc: Make OutputSurface::BindToClient pure virtual and not return bool

cc/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("//build/config/ui.gni")
 import("//testing/test.gni")
 
 component("cc") {
   sources = [
     "animation/animation.cc",
@@ skipping 881 matching lines @@
     "layers/viewport_unittest.cc",
     "output/begin_frame_args_unittest.cc",
     "output/bsp_tree_unittest.cc",
     "output/buffer_to_texture_target_map_unittest.cc",
     "output/compositor_frame_sink_unittest.cc",
     "output/context_cache_controller_unittest.cc",
     "output/filter_operations_unittest.cc",
     "output/gl_renderer_unittest.cc",
     "output/layer_quad_unittest.cc",
     "output/managed_memory_policy_unittest.cc",
-    "output/output_surface_unittest.cc",
     "output/overlay_unittest.cc",
     "output/renderer_pixeltest.cc",
     "output/renderer_settings_unittest.cc",
     "output/shader_unittest.cc",
     "output/software_renderer_unittest.cc",
     "output/texture_mailbox_deleter_unittest.cc",
     "playback/discardable_image_map_unittest.cc",
     "playback/display_item_list_unittest.cc",
     "playback/raster_source_unittest.cc",
     "playback/recording_source_unittest.cc",
@@ skipping 167 matching lines @@
     "//ui/gl:test_support",
   ]
 
   # This target should not require the Chrome executable to run.
   assert_no_deps = [ "//chrome" ]
 
   data = [
     "test/data/",
   ]
 }