Add ProcessControlImpl, the default ProcessControl implementation.

content/content_child.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base',
     '../components/mime_util/mime_util.gyp:mime_util',
     '../components/tracing.gyp:tracing',
     '../components/webcrypto/webcrypto.gyp:webcrypto',
@@ skipping 168 matching lines @@
       'child/permissions/permission_dispatcher_thread_proxy.h',
       'child/permissions/permission_observers_registry.cc',
       'child/permissions/permission_observers_registry.h',
       'child/plugin_message_generator.cc',
       'child/plugin_message_generator.h',
       'child/plugin_messages.h',
       'child/plugin_param_traits.cc',
       'child/plugin_param_traits.h',
       'child/power_monitor_broadcast_source.cc',
       'child/power_monitor_broadcast_source.h',
+      'child/process_control_impl.cc',
+      'child/process_control_impl.h',
       'child/push_messaging/push_dispatcher.cc',
       'child/push_messaging/push_dispatcher.h',
       'child/push_messaging/push_provider.cc',
       'child/push_messaging/push_provider.h',
       'child/quota_dispatcher.cc',
       'child/quota_dispatcher.h',
       'child/quota_message_filter.cc',
       'child/quota_message_filter.h',
       'child/request_extra_data.cc',
       'child/request_extra_data.h',
@@ skipping 134 matching lines @@
         'child/npapi/webplugin_delegate_impl_mac.mm',
       ],
     }],
     ['OS=="win"', {
       'sources!': [
         'child/npapi/webplugin_delegate_impl_aura.cc',
       ],
     }],
   ],
 }