Correct small whitespace inconsistency, lost while renaming variables.
1 'abcdef'.replace(/a(\w+)c/, function() {
2 assertEq(RegExp.lastMatch, 'abc');
3 '123456'.replace(/1(\d+)3/, function() {
4 assertEq(RegExp.lastMatch, '123');
6 assertEq(RegExp.lastMatch, '123');
8 assertEq(RegExp.lastMatch, 'abc');