function compareFcn( a, b ) {
	if ( a === true ) {
		if ( b === true ) {
			return 0;
		}
		return 1;
	}
	if ( b === false ) {
		return 0;
	}
	return -1;
}
Comparison function.

@private
@param {boolean} a - first boolean value for comparison
@param {boolean} b - second boolean value for comparison
@returns {number} comparison result