Oilpan: Enable oilpan for callback classes

Source/core/dom/StringCallback.h

Index: Source/core/dom/StringCallback.h
diff --git a/Source/core/dom/StringCallback.h b/Source/core/dom/StringCallback.h
index 174ef052ef0a5cb94c98ae9888aab23e42b699bc..1e0f8e78490ff3c887f71bd04698e9ab7f193364 100644
--- a/Source/core/dom/StringCallback.h
+++ b/Source/core/dom/StringCallback.h
@@ -38,14 +38,14 @@ namespace blink {
 
 class ExecutionContext;
 
-class StringCallback : public NoBaseWillBeGarbageCollectedFinalized<StringCallback> {
+class StringCallback : public GarbageCollectedFinalized<StringCallback> {
 public:
     virtual ~StringCallback() { }
     virtual void trace(Visitor*) { }
     virtual void handleEvent(const String& data) = 0;
 
     // Helper to post callback task.
-    static void scheduleCallback(PassOwnPtrWillBeRawPtr<StringCallback>, ExecutionContext*, const String& data, const String& instrumentationName);
+    static void scheduleCallback(StringCallback*, ExecutionContext*, const String& data, const String& instrumentationName);
 };
 
 } // namespace blink