fix(jqLite): fix add/remove class in IE9

IE is not my favorite web browser.

this is my take on #5694 
does IE9 parse classes when the attribute is set for SVG elements but not for other elements? (I know className is an object in SVG, but it's weird that this is necessary at all). Would this break SVG class operations for IE9?

In either case, there is a lot of branching happening in this function, what if we just had two versions of the function?