ui: No more TestCompositor. Use NullDraw contexts in unit tests.

ui/compositor/compositor.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,
   },
   'targets': [
     {
@@ skipping 86 matching lines @@
         'test/draw_waiter_for_test.h',
         'test/in_process_context_factory.cc',
         'test/in_process_context_factory.h',
         'test/layer_animator_test_controller.cc',
         'test/layer_animator_test_controller.h',
         'test/test_compositor_host.h',
         'test/test_compositor_host_mac.mm',
         'test/test_compositor_host_ozone.cc',
         'test/test_compositor_host_win.cc',
         'test/test_compositor_host_x11.cc',
-        'test/test_context_factory.cc',
-        'test/test_context_factory.h',
         'test/test_layer_animation_delegate.cc',
         'test/test_layer_animation_delegate.h',
         'test/test_layer_animation_observer.cc',
         'test/test_layer_animation_observer.h',
         'test/test_layers.cc',
         'test/test_layers.h',
         'test/test_suite.cc',
         'test/test_suite.h',
         'test/test_utils.cc',
         'test/test_utils.h',
@@ skipping 45 matching lines @@
               'dependencies': [
                 '<(DEPTH)/base/allocator/allocator.gyp:allocator',
               ],
             }],
           ],
         }],
       ],
     },
   ],
 }