Allow scroll of the canvas if the device height exceeds the available height

Given the following code example...

editor.DeviceManager.add('test', '300px', {
                      height: '1000px',
                      widthMedia: '300px',
});
editor.setDevice("test");

Results in no ability to scroll to top of canvas if editor display area is less than specified height of the device.

See Fiddle for demonstration...

https://jsfiddle.net/gstone007/0vq3o2jf/1/