Parserlib/CSSLint broken in Safari 9

[aartrost]

Hi there,

Parser-lib is broken in Safari 9. This is due to the line field in SyntaxError objects being ignored in favor for the line field in the native Error object that's being used as SyntaxError's prototype.

The error can be easily replicated by validating test, {} on csslint.net in Safari 9. Here's a JSFiddle with a barebones example of where things go wrong: http://jsfiddle.net/c56r7a49/1/. Compare the logged result in Chrome vs Safari 9. The line field in Safari 9 will reflect the line where SyntaxError's prototype is being constructed.