Oilpan: fix build after r201436, r201444.

Source/core/inspector/PageDebuggerAgent.h

 /*
  * Copyright (C) 2011 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 @@
 namespace blink {
 
 class DocumentLoader;
 class InspectorPageAgent;
 class MainThreadDebugger;
 
 class CORE_EXPORT PageDebuggerAgent final
     : public InspectorDebuggerAgent {
     WTF_MAKE_NONCOPYABLE(PageDebuggerAgent);
     WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED(PageDebuggerAgent);
-    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(PageDebuggerAgent);
 public:
     static PassOwnPtrWillBeRawPtr<PageDebuggerAgent> create(MainThreadDebugger*, InspectorPageAgent*, InjectedScriptManager*);
     ~PageDebuggerAgent() override;
     DECLARE_VIRTUAL_TRACE();
 
     void enable(ErrorString*) final;
     void restore() final;
     void compileScript(ErrorString*, const String& expression, const String& sourceURL, bool persistScript, const int* executionContextId, TypeBuilder::OptOutput<TypeBuilder::Debugger::ScriptId>*, RefPtr<TypeBuilder::Debugger::ExceptionDetails>&) override;
     void runScript(ErrorString*, const TypeBuilder::Debugger::ScriptId&, const int* executionContextId, const String* objectGroup, const bool* doNotPauseOnExceptionsAndMuteConsole, RefPtr<TypeBuilder::Runtime::RemoteObject>& result, RefPtr<TypeBuilder::Debugger::ExceptionDetails>&) override;
 
@@ skipping 12 matching lines @@
 
     PageDebuggerAgent(MainThreadDebugger*, InspectorPageAgent*, InjectedScriptManager*);
     RawPtrWillBeMember<InspectorPageAgent> m_pageAgent;
     HashMap<String, String> m_compiledScriptURLs;
 };
 
 } // namespace blink
 
 
 #endif // !defined(PageDebuggerAgent_h)