cc: Split Proxy to eliminate unnecessary dependencies on the impl side

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("//testing/test.gni")
 
 component("cc") {
   sources = [
     "animation/animation.cc",
     "animation/animation.h",
@@ skipping 478 matching lines @@
     "trees/proxy_common.h",
     "trees/proxy_impl.h",
     "trees/proxy_main.h",
     "trees/scoped_abort_remaining_swap_promises.h",
     "trees/single_thread_proxy.cc",
     "trees/single_thread_proxy.h",
     "trees/swap_promise_monitor.cc",
     "trees/swap_promise_monitor.h",
     "trees/thread_proxy.cc",
     "trees/thread_proxy.h",
+    "trees/thread_verifier.cc",
+    "trees/thread_verifier.h",
     "trees/threaded_channel.cc",
     "trees/threaded_channel.h",
     "trees/tree_synchronizer.cc",
     "trees/tree_synchronizer.h",
   ]
 
   if (target_cpu == "x86" || target_cpu == "x64") {
     sources += [
       "raster/texture_compressor_etc1_sse.cc",
       "raster/texture_compressor_etc1_sse.h",
@@ skipping 44 matching lines @@
     "test/fake_delegated_renderer_layer.h",
     "test/fake_delegated_renderer_layer_impl.cc",
     "test/fake_delegated_renderer_layer_impl.h",
     "test/fake_display_list_raster_source.cc",
     "test/fake_display_list_raster_source.h",
     "test/fake_display_list_recording_source.cc",
     "test/fake_display_list_recording_source.h",
     "test/fake_external_begin_frame_source.cc",
     "test/fake_external_begin_frame_source.h",
     "test/fake_impl_proxy.h",
+    "test/fake_impl_thread_verifier.h",
     "test/fake_layer_tree_host.cc",
     "test/fake_layer_tree_host.h",
     "test/fake_layer_tree_host_client.cc",
     "test/fake_layer_tree_host_client.h",
     "test/fake_layer_tree_host_impl.cc",
     "test/fake_layer_tree_host_impl.h",
     "test/fake_layer_tree_host_impl_client.cc",
     "test/fake_layer_tree_host_impl_client.h",
     "test/fake_output_surface.cc",
     "test/fake_output_surface.h",
@@ skipping 352 matching lines @@
     "//ui/gl",
     "//ui/gl:test_support",
   ]
 
   if (is_android) {
     isolate_file = "cc_perftests.isolate"
   }
 }
 # When adding support for isolates, please have a look at run-time dependencies
 # in the cc_unittests_run target in cc_tests.gyp.