Actually start ServiceWorkerThread in EmbeddedWorker

Source/web/web.gypi

 {
   'variables': {
     'web_files': [
       'ApplicationCacheHost.cpp',
       'ApplicationCacheHostInternal.h',
       'AssertMatchingEnums.cpp',
       'AssociatedURLLoader.cpp',
       'AssociatedURLLoader.h',
       'AutofillPopupMenuClient.cpp',
       'AutofillPopupMenuClient.h',
@@ skipping 65 matching lines @@
       'PopupContainer.cpp',
       'PopupContainer.h',
       'PopupListBox.cpp',
       'PopupListBox.h',
       'PopupMenuChromium.cpp',
       'PopupMenuChromium.h',
       'PrerendererClientImpl.cpp',
       'PrerendererClientImpl.h',
       'ScrollbarGroup.cpp',
       'ScrollbarGroup.h',
+      'ServiceWorkerGlobalScopeProxy.cpp',
+      'ServiceWorkerGlobalScopeProxy.h',
       'SharedWorkerRepositoryClientImpl.cpp',
       'SharedWorkerRepositoryClientImpl.h',
       'SpeechInputClientImpl.cpp',
       'SpeechInputClientImpl.h',
       'SpeechRecognitionClientProxy.cpp',
       'SpeechRecognitionClientProxy.h',
       'SpellCheckerClientImpl.cpp',
       'SpellCheckerClientImpl.h',
       'StorageAreaProxy.cpp',
       'StorageAreaProxy.h',
@@ skipping 273 matching lines @@
         {
           'web_unittest_files': [
             'tests/KeyCodeConversionTestGtk.cpp',
             'tests/WebInputEventFactoryTestGtk.cpp',
           ],
         }
       ],
     ],
   },
 }