[wrapper-tracing] Enable cleanup and invalidating on WorkerBackingThread

third_party/WebKit/Source/platform/heap/ThreadState.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 419 matching lines @@
   void shouldFlushHeapDoesNotContainCache() {
     m_shouldFlushHeapDoesNotContainCache = true;
   }
 
   void registerTraceDOMWrappers(
       v8::Isolate* isolate,
       void (*traceDOMWrappers)(v8::Isolate*, Visitor*),
       void (*invalidateDeadObjectsInWrappersMarkingDeque)(v8::Isolate*),
       void (*performCleanup)(v8::Isolate*)) {
     m_isolate = isolate;
+    DCHECK(!m_isolate || traceDOMWrappers);
+    DCHECK(!m_isolate || invalidateDeadObjectsInWrappersMarkingDeque);
+    DCHECK(!m_isolate || performCleanup);
     m_traceDOMWrappers = traceDOMWrappers;
     m_invalidateDeadObjectsInWrappersMarkingDeque =
         invalidateDeadObjectsInWrappersMarkingDeque;
     m_performCleanup = performCleanup;
   }
 
   // By entering a gc-forbidden scope, conservative GCs will not
   // be allowed while handling an out-of-line allocation request.
   // Intended used when constructing subclasses of GC mixins, where
   // the object being constructed cannot be safely traced & marked
@@ skipping 322 matching lines @@
 class ThreadStateFor<AnyThread> {
   STATIC_ONLY(ThreadStateFor);
 
  public:
   static ThreadState* state() { return ThreadState::current(); }
 };
 
 }  // namespace blink
 
 #endif  // ThreadState_h