Gamepad API: add support for gamepadconnected and gamepaddisconnected events

Source/web/FrameLoaderClientImpl.cpp

Index: Source/web/FrameLoaderClientImpl.cpp
diff --git a/Source/web/FrameLoaderClientImpl.cpp b/Source/web/FrameLoaderClientImpl.cpp
index 8cdf3ebcc1b5da2e7c7f3d9fbec2203351d7f057..447f0c4e6545d573bd6ec1b4d98e246b5dc086d2 100644
--- a/Source/web/FrameLoaderClientImpl.cpp
+++ b/Source/web/FrameLoaderClientImpl.cpp
@@ -74,6 +74,7 @@
 #include "core/rendering/HitTestResult.h"
 #include "modules/device_orientation/DeviceMotionController.h"
 #include "modules/device_orientation/DeviceOrientationController.h"
+#include "modules/gamepad/NavigatorGamepad.h"
 #include "modules/screen_orientation/ScreenOrientationController.h"
 #include "platform/MIMETypeRegistry.h"
 #include "platform/UserGestureIndicator.h"
@@ -123,6 +124,8 @@ void FrameLoaderClientImpl::dispatchDidClearWindowObjectInWorld(DOMWrapperWorld*
                 DeviceOrientationController::from(*document);
             if (RuntimeEnabledFeatures::screenOrientationEnabled())
                 ScreenOrientationController::from(*document);
+            if (RuntimeEnabledFeatures::gamepadEnabled() && document->domWindow())
+                NavigatorGamepad::from(document->domWindow()->navigator());
         }
     }
 }