Follows-up f354aafebc.
Avoid forced style calculation during page load. Instead calculate
in the very next animation frame. This is only a few ms later, but
makes a big difference by doing this outside the critical path.
Change-Id: I5805958781bf64d1e4a30f441ed7f57807072284
We were adding a .first CSS class to the portlet from JavaScript
instead of just using a smarter selector, which caused the incorrectly
styled portlet to visibly flash sometimes.
This was only useful for IE 6 (even IE 7 supports the sibling selector
'+', which we can use here), and we don't serve JavaScript to it
anymore. It would be neater to use ':first-of-type', but that's not as
widely supported.
Bug: T89542
Change-Id: I1904b3899c43bca52a6c996b8ce08c8bdf764aa0
