[Mac] Keep the page-info-bubble controller alive until done with layout.

[Mac] Keep the page-info-bubble controller alive until done with layout.

If the window is animating closed when a previously-posted
PerformLayout task is fired, the last reference to the controller may
be released while laying things out.  Pin the controller down until
the task is completed.

BUG=90773
TEST=Monitor crash server for continued zombies.


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=98285

[Scott Hess - ex-Googler, 2011-08-24 17:28:07]

I locally added code to log [controller_ retainCount] at entry and exit from
PerformLayout(), and, indeed, I've had multiple cases where the retain count on
exit (before the scoper fired) was 1.  So this seems to handle it.

[Robert Sesek, 2011-08-24 18:10:30]

LGTM

[commit-bot: I haz the power, 2011-08-25 20:27:42]

Change committed as 98285