Add a mojoPrivate API that exposes mojo to component apps/extensions.

extensions/extensions.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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 1255 matching lines @@
         'common/one_shot_event_unittest.cc',
         'common/permissions/api_permission_set_unittest.cc',
         'common/permissions/manifest_permission_set_unittest.cc',
         'common/permissions/socket_permission_unittest.cc',
         'common/permissions/usb_device_permission_unittest.cc',
         'common/stack_frame_unittest.cc',
         'common/url_pattern_set_unittest.cc',
         'common/url_pattern_unittest.cc',
         'common/user_script_unittest.cc',
         'renderer/activity_log_converter_strategy_unittest.cc',
+        'renderer/api/mojo_private/mojo_private_unittest.cc',
         'renderer/api/serial/data_receiver_unittest.cc',
         'renderer/api/serial/data_sender_unittest.cc',
         'renderer/api/serial/serial_api_unittest.cc',
         'renderer/api_test_base.cc',
         'renderer/api_test_base.h',
         'renderer/api_test_base_unittest.cc',
         'renderer/event_unittest.cc',
         'renderer/json_schema_unittest.cc',
         'renderer/mojo/keep_alive_client_unittest.cc',
         'renderer/messaging_utils_unittest.cc',
@@ skipping 10 matching lines @@
       'conditions': [
         ['OS=="win" and win_use_allocator_shim==1', {
           'dependencies': [
             '../base/allocator/allocator.gyp:allocator',
           ],
         }],
       ],
     },
   ]
 }