[worklets] Split up InProcessWorkerMessagingProxy into a base+worker class.

third_party/WebKit/Source/web/DedicatedWorkerGlobalScopeProxyProviderImpl.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
     , public DedicatedWorkerGlobalScopeProxyProvider {
     USING_GARBAGE_COLLECTED_MIXIN(DedicatedWorkerGlobalScopeProxyProviderImpl);
     WTF_MAKE_NONCOPYABLE(DedicatedWorkerGlobalScopeProxyProviderImpl);
 public:
     static DedicatedWorkerGlobalScopeProxyProviderImpl* create()
     {
         return new DedicatedWorkerGlobalScopeProxyProviderImpl();
     }
 
     ~DedicatedWorkerGlobalScopeProxyProviderImpl() override { }
-    InProcessWorkerGlobalScopeProxy* createWorkerGlobalScopeProxy(Worker*) override;
+    InProcessWorkerMessagingProxy* createWorkerGlobalScopeProxy(Worker*) override;
 
     DEFINE_INLINE_VIRTUAL_TRACE() { DedicatedWorkerGlobalScopeProxyProvider::trace(visitor); }
 
 private:
     DedicatedWorkerGlobalScopeProxyProviderImpl() { }
 };
 
 } // namespace blink
 
 #endif // DedicatedWorkerGlobalScopeProxyProviderImpl_h