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

Source/core/core.gypi

 {
     'includes': [
       'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/Animation.idl',
             'animation/AnimationEffect.idl',
             'animation/AnimationPlayer.idl',
@@ skipping 1129 matching lines @@
             'frame/DOMWindowLifecycleNotifier.cpp',
             'frame/DOMWindowLifecycleNotifier.h',
             'frame/DOMWindowLifecycleObserver.cpp',
             'frame/DOMWindowLifecycleObserver.h',
             'frame/DOMWindowProperty.cpp',
             'frame/DOMWindowProperty.h',
             'frame/DOMWindowTimers.cpp',
             'frame/DOMWindowTimers.h',
             'frame/DeprecatedScheduleStyleRecalcDuringLayout.cpp',
             'frame/DeprecatedScheduleStyleRecalcDuringLayout.h',
-            'frame/DeviceEventControllerBase.cpp',
-            'frame/DeviceEventControllerBase.h',
-            'frame/DeviceEventDispatcherBase.cpp',
-            'frame/DeviceEventDispatcherBase.h',
             'frame/DeviceSingleWindowEventController.cpp',
             'frame/DeviceSingleWindowEventController.h',
             'frame/EventHandlerRegistry.cpp',
             'frame/EventHandlerRegistry.h',
+            'frame/PlatformEventController.cpp',
+            'frame/PlatformEventController.h',
+            'frame/PlatformEventDispatcher.cpp',
+            'frame/PlatformEventDispatcher.h',
             'frame/Frame.cpp',
             'frame/Frame.h',
             'frame/FrameConsole.cpp',
             'frame/FrameDestructionObserver.cpp',
             'frame/FrameDestructionObserver.h',
             'frame/FrameHost.cpp',
             'frame/FrameHost.h',
             'frame/FrameOwner.h',
             'frame/FrameView.cpp',
             'frame/History.cpp',
@@ skipping 2260 matching lines @@
             'rendering/RenderTableCellTest.cpp',
             'rendering/RenderTableRowTest.cpp',
             'rendering/shapes/BoxShapeTest.cpp',
             'testing/PrivateScriptTestTest.cpp',
             'testing/UnitTestHelpers.cpp',
             'testing/UnitTestHelpers.h',
             'xml/parser/SharedBufferReaderTest.cpp',
         ],
     }
 }