Minified JS not parseable by Firefox .. webkit works :: error: SyntaxError: invalid regular expression flag r"

```
Minify commit/version: 2.1.7
PHP version: 5.4.24

I have a lot of JS and when I minify it, it breaks. It cannot be parsed by 
Firefox anymore

the error is: "SyntaxError: invalid regular expression flag r"

--- 

I dont have a minimal sample yet but ill try to produce that as well

```

Original issue reported on code.google.com by `Pich.Dom...@gmail.com` on 6 Apr 2014 at 2:09
