FBTF: Allow forward declaration of classes passed to sync IPC messages.

chrome/chrome_common.gypi

 # Copyright (c) 2010 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': {
     'variables': {
       'chrome_common_target': 0,
     },
     'target_conditions': [
@@ skipping 266 matching lines @@
         'common/url_constants.h',
         'common/utility_messages.cc',
         'common/utility_messages.h',
         'common/utility_messages_internal.h',
         'common/view_types.cc',
         'common/view_types.h',
         'common/visitedlink_common.cc',
         'common/visitedlink_common.h',
         'common/web_database_observer_impl.cc',
         'common/web_database_observer_impl.h',
+        'common/webkit_param_traits.cc',
         'common/webkit_param_traits.h',
         'common/webmessageportchannel_impl.cc',
         'common/webmessageportchannel_impl.h',
         'common/window_container_type.cc',
         'common/window_container_type.h',
         'common/worker_messages.cc',
         'common/worker_messages.h',
         'common/worker_messages_internal.h',
         'common/worker_thread_ticker.cc',
         'common/worker_thread_ticker.h',
@@ skipping 137 matching lines @@
           'configurations': {
             'Common_Base': {
               'msvs_target_platform': 'x64',
             },
           },
         },
       ],
     }],
   ],
 }