Remove duplicate switch case
Remove duplicate switch case

Guessing this one was the result of a bad merge?

sourcelair/xterm.js,sourcelair/xterm.js,xtermjs/xterm.js,Tyriar/xterm.js,Tyriar/xterm.js,Tyriar/xterm.js,xtermjs/xterm.js,xtermjs/xterm.js,sourcelair/xterm.js,sourcelair/xterm.js,Tyriar/xterm.js,xtermjs/xterm.js,Tyriar/xterm.js,xtermjs/xterm.js