Add mock classes for Bus, ObjectProxy, and ExportedObject.

dbus/dbus.gyp

 # Copyright (c) 2011 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': [
     {
       'target_name': 'dbus',
       'type': 'static_library',
       'dependencies': [
         '../base/base.gyp:base',
         '../build/linux/system.gyp:dbus',
       ],
       'sources': [
         'bus.cc',
         'bus.h',
+        'exported_object.cc',
         'exported_object.h',
-        'exported_object.cc',
         'message.cc',
         'message.h',
         'object_proxy.cc',
         'object_proxy.h',
         'scoped_dbus_error.h',
       ],
     },
     {
+      # This target contains mocks that can be used to write unit tests
+      # without issuing actual D-Bus calls.
+      'target_name': 'dbus_test_support',
+      'type': 'static_library',
+      'dependencies': [
+        '../build/linux/system.gyp:dbus',
+        '../testing/gmock.gyp:gmock',
+        'dbus',
+      ],
+      'sources': [
+        'mock_bus.cc',
+        'mock_bus.h',
+        'mock_object_proxy.cc',
+        'mock_object_proxy.h',
+      ],
+      'include_dirs': [
+        '..',
+      ],
+    },
+    {
       'target_name': 'dbus_unittests',
       'type': 'executable',
       'dependencies': [
+        '../base/base.gyp:test_support_base',
+        '../build/linux/system.gyp:dbus',
+        '../testing/gmock.gyp:gmock',
+        '../testing/gtest.gyp:gtest',
         'dbus',
-        '../base/base.gyp:test_support_base',
-        '../testing/gtest.gyp:gtest',
-        '../build/linux/system.gyp:dbus',
+        'dbus_test_support',
       ],
       'sources': [
         '../base/test/run_all_unittests.cc',
         'bus_unittest.cc',
-        'message_unittest.cc',
         'end_to_end_async_unittest.cc',
         'end_to_end_sync_unittest.cc',
+        'message_unittest.cc',
+        'mock_unittest.cc',
         'test_service.cc',
         'test_service.h',
       ],
       'include_dirs': [
         '..',
       ],
     },
   ],
 }