wrapAngelMatcher function
Returns an AngelMatcher that represents x.
If x is an AngelMatcher, then it is returned, unmodified.
Implementation
AngelMatcher wrapAngelMatcher(Object x) {
if (x is AngelMatcher) return x;
if (x is ContextAwareMatcher) return _WrappedAngelMatcher(x);
return wrapAngelMatcher(wrapContextAwareMatcher(x));
}