fixed QSA testing (mistyped 'removeChild') and improved tests node removal, reduced code by embedding isXML(), isQuirks() and isQuirksBuggy() method calls in the 'switchContext()' method which is called once each time the queried host environment changes
fixed QSA testing (mistyped 'removeChild') and improved tests node removal, reduced code by embedding isXML(), isQuirks() and isQuirksBuggy() method calls in the 'switchContext()' method which is called once each time the queried host environment changes

dperini/nwmatcher,dperini/nwmatcher,dperini/nwmatcher