Fix IE 9 load regression (seen on flickr.com) with YUI 3.5 and IE 9 on quirks-mode pages

[scottschiller]

We flipped YUI 3.5 and noted a report of IE 9 users not getting YUI3 JS modules loading.

It appears that when IE 9 is on a quirks mode page or has manually been flipped to a mode other than IE 9 standards, <script>.onload does not fire, only <script>.onreadystatechange works. (We're not proud of the fact we have a few quirks-mode pages still kicking around, but that's a story for another time.)

YUI appears to have logic that applies onreadystatechange for IE 6, 7 and 8, but did not also include IE 9 (and potentially IE 10+?) when not in standards mode.

Minimal test case, should illustrate current bug with 3.5.1 (view under IE 9 - note if you switch rendering modes to IE 9 standards, things will start working):
https://gist.github.com/2632058

If you wanted to be paranoid, you could probably get away with attaching both onreadystatechange + onload on <script> and clear/remove both events when one fires.

Side note: build.sh was ran before this commit, so some other lines appear to have been updated as a result.

Second note: I'm a pull request n00b, so apologies if I missed any expected things.

As always, thanks for YUI. It's excellent and we're big fans.

[travisbot]

This pull request passes (merged 050ebaa into 990e9c8).

[sdesai]

Thanks Scott.

We'll fit this into the next release. Here's a report for it: http://yuilibrary.com/projects/yui3/ticket/2532246 (it came in too late for inclusion in 3.5.1, given the quirksmode edge case).

[scottschiller]

Excellent. I plan to apply this as patch to our copy of 3.5, so we can upgrade Flickr in the meantime.
I think my change is correct, but let me know if you find any holes in my logic.

[davglass]

I've already merged this in locally and rebuilt the files. It will go into the next build that I can push to.

[davglass]

Meant to just comment on it l)

[travisbot]

This pull request passes (merged 050ebaa into 990e9c8).