Gamepad constructor
Creates a new Gamepad manager.
It automatically listens for gamepad connection and disconnection events and attempts to map connected gamepads to available ports.
Typically, you don't instantiate this class yourself. Instead, you use
the app.gamepad member provided by the App class.
Implementation
Gamepad() {
web.window.addEventListener('gamepadconnected', _connectGamepadHandler.toJS);
web.window.addEventListener('gamepaddisconnected', _disconnectGamepadHandler.toJS);
for (var gamepad in _getGamepads()) {
_connectGamepad(gamepad);
}
}