Enhanced HTML test look & feel, thanks to John Evans

Enhanced HTML test look & feel, thanks to John Evans
https://github.com/dart-lang/dart/pull/3

Much of this was originally reviewed by me in pull #1:
https://github.com/dart-lang/dart/pull/1

Committed: https://code.google.com/p/dart/source/detail?r=6817

[Jennifer Messerly, 2012-04-20 23:29:21]

LGTM. I added Siggi in case he has more thoughts on it with respect to the newly
refactored HTML tests. But I'm going to submit because I tried it out and it's
pretty nice even in its current form.

Also I made the code break at 80 cols to match up with our style rules. Let me
know John if you'd prefer to do this yourself in future patches... I hope it
doesn't mess up the merge too much. And thanks!

[prujohn, 2012-04-20 23:40:54]

On 2012/04/20 23:29:21, John Messerly wrote:
> 
> Also I made the code break at 80 cols to match up with our style >rules.

I'll remember that 80 cols next time.  Sorry for the extra work. 

Glad you like it!

[Siggi Cherem (dart-lang), 2012-04-21 00:02:13]

https://chromiumcodereview.appspot.com/10168022/diff/4001/lib/unittest/html_e...
File lib/unittest/html_enhanced_config.dart (right):

https://chromiumcodereview.appspot.com/10168022/diff/4001/lib/unittest/html_e...
lib/unittest/html_enhanced_config.dart:232: static bool get _isIE() =>
document.window.navigator.userAgent.contains('MSIE');
still a few more lines with > 80 (here and below)

[Siggi Cherem (dart-lang), 2012-04-21 00:02:45]

Very cool to see this coming in!

[Siggi Cherem (dart-lang), 2012-04-24 23:26:30]

https://chromiumcodereview.appspot.com/10168022/diff/4001/lib/unittest/html_e...
File lib/unittest/html_enhanced_config.dart (right):

https://chromiumcodereview.appspot.com/10168022/diff/4001/lib/unittest/html_e...
lib/unittest/html_enhanced_config.dart:133: .replaceAll("(?:[^a-z0-9
]|(?<=['\"])s)",'_')
Can you help me understand this expression better. The non-capture and
lookbehind is a bit confusing.

I run into a test where groups used parenthesis, and I'd like to fix this to
also replace them with _.