Introduce PlatformEvent to handle Device events, Battery events and Gamepad events.

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 154 matching lines @@
     Gamepad* gamepad = m_pendingEvents.takeFirst();
     const AtomicString& eventName = gamepad->connected() ? EventTypeNames::gamepadconnected : EventTypeNames::gamepaddisconnected;
     window()->dispatchEvent(GamepadEvent::create(eventName, false, true, gamepad));
 
     if (!m_pendingEvents.isEmpty())
         m_dispatchOneEventRunner.runAsync();
 }
 
 NavigatorGamepad::NavigatorGamepad(LocalFrame* frame)
     : DOMWindowProperty(frame)
-    , DeviceEventControllerBase(frame ? frame->page() : 0)
+    , PlatformEventController(frame ? frame->page() : 0)
     , DOMWindowLifecycleObserver(frame ? frame->domWindow() : 0)
     , m_dispatchOneEventRunner(this, &NavigatorGamepad::dispatchOneEvent)
 {
 }
 
 NavigatorGamepad::~NavigatorGamepad()
 {
 }
 
 const char* NavigatorGamepad::supplementName()
@@ skipping 98 matching lines @@
         if (connectedGamepadChanged || (!oldWasConnected && newIsConnected)) {
             m_pendingEvents.append(newGamepad);
         }
     }
 
     if (!m_pendingEvents.isEmpty())
         m_dispatchOneEventRunner.runAsync();
 }
 
 } // namespace blink