Use InputHandler method of click handling instead of current one in SinglePlayerButton

[Fastjur]

No description provided.

[Wolgo]

SinglePlayerButton extends Button, the onclick of button is called by doUpdate() which already uses if(InputHandler.isLeftMouseButtonDown) . Is there something wrong with this?

[grappigegovert]

Looks okay to me, there only are some unnecessary debug messages left

[Fastjur]

Hmm. It was my impression that SinglePlayerButton still used an old implementation because it spams the debug info. However the other button does to. This was probably some lag on my end when testing with other buttons. This does raise the question. Do we want the contains method to be spammed like this or should we prevent this?