Mojo: Add the ability to hook up a channel to the embedder API.

mojo/mojo.gyp

 # Copyright 2013 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.
 
 {
   'target_defaults': {
     'conditions': [
       ['mojo_shell_debug_url != ""', {
         'defines': [
           'MOJO_SHELL_DEBUG=1',
@@ skipping 140 matching lines @@
         'mojo_common_test_support',
         'mojo_system',
         'mojo_system_impl',
       ],
       'sources': [
         'system/core_impl_unittest.cc',
         'system/core_test_base.cc',
         'system/core_test_base.h',
         'system/data_pipe_unittest.cc',
         'system/dispatcher_unittest.cc',
+        'system/embedder_unittest.cc',
         'system/local_data_pipe_unittest.cc',
         'system/message_pipe_dispatcher_unittest.cc',
         'system/message_pipe_unittest.cc',
         'system/multiprocess_message_pipe_unittest.cc',
         'system/raw_channel_posix_unittest.cc',
         'system/remote_message_pipe_posix_unittest.cc',
         'system/simple_dispatcher_unittest.cc',
+        'system/test_embedder.cc',
+        'system/test_embedder.h',
         'system/test_utils.cc',
         'system/test_utils.h',
         'system/waiter_list_unittest.cc',
         'system/waiter_test_utils.cc',
         'system/waiter_test_utils.h',
         'system/waiter_unittest.cc',
       ],
     },
     {
       'target_name': 'mojo_gles2',
@@ skipping 297 matching lines @@
             'java_in_dir': '<(DEPTH)/mojo/shell/android/apk',
             'resource_dir': '<(DEPTH)/mojo/shell/android/apk/res',
             'native_lib_target': 'libmojo_shell',
           },
           'includes': [ '../build/java_apk.gypi' ],
         }
       ],
     }],
   ],
 }