Limit the usage of SharedPersistent to ScriptValue only

Source/bindings/v8/ScriptController.h

Index: Source/bindings/v8/ScriptController.h
diff --git a/Source/bindings/v8/ScriptController.h b/Source/bindings/v8/ScriptController.h
index 403c43df50f2f435760fd318c9e925faa6c7878d..08a8fe3d3e92dd9afea63de801296e92d3af6992 100644
--- a/Source/bindings/v8/ScriptController.h
+++ b/Source/bindings/v8/ScriptController.h
@@ -32,8 +32,6 @@
 #define ScriptController_h
 
 #include "bindings/v8/ScriptValue.h"
-#include "bindings/v8/SharedPersistent.h"
-
 #include "core/fetch/CrossOriginAccessControl.h"
 #include "wtf/Forward.h"
 #include "wtf/HashMap.h"
@@ -110,7 +108,7 @@ public:
     // Creates a property of the global object of a frame.
     void bindToWindowObject(Frame*, const String& key, NPObject*);
 
-    PassRefPtr<SharedPersistent<v8::Object> > createPluginWrapper(Widget*);
+    ScriptValue createPluginWrapper(Widget*);
 
     void enableEval();
     void disableEval(const String& errorMessage);