Stop firing orientationchange events at pages that are not visible

Source/core/dom/FullscreenObserver.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 InspectorNodeIds_h
-#define InspectorNodeIds_h
+#ifndef FullscreenObserver_h
+#define FullscreenObserver_h
 
 namespace WebCore {
 
-class Node;
+class FullscreenObserver {
+public:
+    virtual void didFullyExitFullscreen() = 0;
 
-class InspectorNodeIds {
-public:
-    static int idForNode(Node*);
-    static Node* nodeForId(int);
+    virtual ~FullscreenObserver() { }
 };
 
 } // namespace WebCore
 
-
-#endif // !defined(InspectorNodeIds_h)
+#endif // FullscreenObserver_h