Skip empty () and , not processing closing token a second time
This should speed this sniff up, without changing anything. When an empty
() or  is detected, the closing parentesis is skipped and not processed
a second time. Because of this, the processCloseParenthesis does not need
to check if the previous token is an open parentesis (this can't happen
I did a profile run and it turns out the SpaceyParenthesis sniff is the
slowest in this code base right now. That's why I'm here trying to
speed it up.