Pass implementation object to supplemental classes by reference

Source/modules/screen_orientation/ScreenOrientation.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ScreenOrientation_h
 #define ScreenOrientation_h
 
 #include "core/events/EventTarget.h"
 #include "core/frame/DOMWindowProperty.h"
 #include "platform/Supplementable.h"
 #include "wtf/Vector.h"
 #include "wtf/text/AtomicString.h"
 #include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
 class Screen;
 
 class ScreenOrientation FINAL : public Supplement<Screen>, DOMWindowProperty {
 public:
-    static ScreenOrientation* from(Screen*);
+    static ScreenOrientation& from(Screen&);
     virtual ~ScreenOrientation();
 
     DEFINE_STATIC_ATTRIBUTE_EVENT_LISTENER(orientationchange);
 
-    static const AtomicString& orientation(Screen*);
-    static bool lockOrientation(Screen*, const Vector<String>& orientations);
-    static bool lockOrientation(Screen*, const AtomicString& orientation);
-    static void unlockOrientation(Screen*);
+    static const AtomicString& orientation(Screen&);
+    static bool lockOrientation(Screen&, const Vector<String>& orientations);
+    static bool lockOrientation(Screen&, const AtomicString& orientation);
+    static void unlockOrientation(Screen&);
 
 private:
-    explicit ScreenOrientation(Screen*);
+    explicit ScreenOrientation(Screen&);
     static const char* supplementName();
     Screen* screen() const;
 };
 
 } // namespace WebCore
 
 #endif // ScreenOrientation_h