Replaced TestNowSource with SimpleTestTickClock.

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 655 matching lines @@
     "test/test_context_support.cc",
     "test/test_context_support.h",
     "test/test_gles2_interface.cc",
     "test/test_gles2_interface.h",
     "test/test_gpu_memory_buffer_manager.cc",
     "test/test_gpu_memory_buffer_manager.h",
     "test/test_image_factory.cc",
     "test/test_image_factory.h",
     "test/test_in_process_context_provider.cc",
     "test/test_in_process_context_provider.h",
-    "test/test_now_source.cc",
-    "test/test_now_source.h",
     "test/test_occlusion_tracker.h",
     "test/test_shared_bitmap_manager.cc",
     "test/test_shared_bitmap_manager.h",
     "test/test_task_graph_runner.cc",
     "test/test_task_graph_runner.h",
     "test/test_texture.cc",
     "test/test_texture.h",
     "test/test_tile_priorities.cc",
     "test/test_tile_priorities.h",
     "test/test_web_graphics_context_3d.cc",
@@ skipping 234 matching lines @@
     "//ui/gfx/geometry",
     "//ui/gl",
   ]
 
   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.