Have bindings layer assume and insist that all interface types are GCed.

third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h

Index: third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h b/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
index b3c1f7949df0bdec45cd4844aa0f934696e44c69..62484cd14861a310549c7111a919b2e2a084a0b8 100644
--- a/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
+++ b/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
@@ -215,23 +215,16 @@ private:
 };
 
 template<>
-inline void DOMWrapperMap<ScriptWrappable>::PersistentValueMapTraits::Dispose(v8::Isolate*, v8::Global<v8::Object> value, ScriptWrappable* key)
+inline void DOMWrapperMap<ScriptWrappable>::PersistentValueMapTraits::Dispose(v8::Isolate*, v8::Global<v8::Object> value, ScriptWrappable*)
 {
-    auto wrapperTypeInfo = toWrapperTypeInfo(value);
-    if (wrapperTypeInfo->isGarbageCollected())
-        wrapperTypeInfo->derefObject();
-    else
-        wrapperTypeInfo->derefObject(toScriptWrappable(value));
+    toWrapperTypeInfo(value)->wrapperDestroyed();
 }
 
 template<>
 inline void DOMWrapperMap<ScriptWrappable>::PersistentValueMapTraits::DisposeWeak(const v8::WeakCallbackInfo<WeakCallbackDataType>& data)
 {
     auto wrapperTypeInfo = reinterpret_cast<WrapperTypeInfo*>(data.GetInternalField(v8DOMWrapperTypeIndex));
-    if (wrapperTypeInfo->isGarbageCollected())
-        wrapperTypeInfo->derefObject();
-    else
-        wrapperTypeInfo->derefObject(KeyFromWeakCallbackInfo(data));
+    wrapperTypeInfo->wrapperDestroyed();
 }
 
 } // namespace blink