Revert of Notify the browser when the page lost interest about gamepads

Source/modules/gamepad/NavigatorGamepad.cpp

 /*
  * Copyright (C) 2011, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 210 matching lines @@
         && !window->hasEventListeners(EventTypeNames::gamepaddisconnected)) {
         m_hasEventListener = false;
     }
 }
 
 void NavigatorGamepad::didRemoveAllEventListeners(LocalDOMWindow*)
 {
     m_hasEventListener = false;
 }
 
-void NavigatorGamepad::pageVisibilityChanged()
-{
-    // We inform the embedder whether it needs to provide gamepad data for us.
-    // In this sense it is irrelevant whether we need an event listener hence there is no check here.
-    if (page()->visibilityState() == PageVisibilityStateVisible)
-        startUpdating();
-    else
-        stopUpdating();
-}
-
 } // namespace WebCore