function onPredicate( error, result ) {
		if ( error ) {
			return done( error );
		}
		if ( !result ) {
			return fcn.call( thisArg, idx, next );
		}
		if ( args.length ) {
			args.unshift( null ); // error argument
		}
		done.apply( null, args );
	}
Callback invoked upon a predicate result.

@private
@param {(Error|null)} error - error object
@param {boolean} result - predicate result
@returns {void}