Add Mojo application test support to Chromium.

mojo/mojo_base.gyp

 # 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.
 
 # Essential components (and their tests) that are needed to build
 # Chrome should be here.  Other components that are useful only in
 # Mojo land like mojo_shell should be in mojo.gyp.
 {
   'includes': [
     'mojo_variables.gypi',
@@ skipping 115 matching lines @@
         '../base/base.gyp:base',
         '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         'mojo_common_lib',
         '<(mojo_system_for_component)',
       ],
       'sources': [
         'environment/default_async_waiter_impl.cc',
         'environment/default_async_waiter_impl.h',
         'environment/default_logger_impl.cc',
         'environment/default_logger_impl.h',
+        'environment/default_run_loop_impl.cc',
+        'environment/default_run_loop_impl.h',
       ],
       'include_dirs': [
         '..',
       ],
     },
     {
      # GN version: //mojo/application
      'target_name': 'mojo_application_chromium',
      'type': 'static_library',
      'sources': [
@@ skipping 64 matching lines @@
           ],
           'variables': {
             'java_in_dir': '<(DEPTH)/mojo/android/system',
           },
           'includes': [ '../build/java.gypi' ],
         },
       ]
     }]
   ]
 }