blink: Cleanup class forward declarations

third_party/WebKit/Source/modules/serviceworkers/InstallEvent.h

 // Copyright 2015 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.
 
 #ifndef InstallEvent_h
 #define InstallEvent_h
 
 #include "modules/EventModules.h"
 #include "modules/ModulesExport.h"
 #include "modules/serviceworkers/ExtendableEvent.h"
 #include "modules/serviceworkers/ForeignFetchOptions.h"
 
 namespace blink {
 
-class USVStringOrUSVStringSequence;
-
 class MODULES_EXPORT InstallEvent : public ExtendableEvent {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   static InstallEvent* create(const AtomicString& type,
                               const ExtendableEventInit&);
   static InstallEvent* create(const AtomicString& type,
                               const ExtendableEventInit&,
                               WaitUntilObserver*);
 
   ~InstallEvent() override;
 
   void registerForeignFetch(ExecutionContext*,
                             const ForeignFetchOptions&,
                             ExceptionState&);
 
   const AtomicString& interfaceName() const override;
 
  protected:
   InstallEvent(const AtomicString& type, const ExtendableEventInit&);
   InstallEvent(const AtomicString& type,
                const ExtendableEventInit&,
                WaitUntilObserver*);
 };
 
 }  // namespace blink
 
 #endif  // InstallEvent_h