Add pixel testing for infobars.

This globally disables animations when pixel verification is enabled.

Bug: none
Change-Id: Ifb523039dddb2d5cd3b9a767bd847f6ee515c385
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4558724


Reviewed-by: Sven Zheng <svenzheng@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Sven Zheng <svenzheng@chromium.org>
Code-Coverage: Findit <findit-for-me@appspot.gserviceaccount.com>
Auto-Submit: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1148622}