code: public boolean remove(final VisitState k) {
  		// The starting point.
  		int pos = (int)(MurmurHash3.hash(k.schemeAuthority) & mask);
  		// There's always an unused entry.
  		while (visitState[pos] != null) {
  			if (visitState[pos] == k) {
  				size--;
  				shiftKeys(pos);
  				// TODO: implement resize
  				return true;
  			}
  			pos = (pos + 1) & mask;
  		}
  		return false;
  	}
docs: Removes a given visit state.
  
  @param k the visit state to be removed.
  @return true if the state set changed as a result of this operation.