Add super.dispose to WebglRenderer.dispose
Add super.dispose to WebglRenderer.dispose

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