Add WebDX for long animation frames & page visibility state
Using existing UseCounters.
Change-Id: I0649ef64e6e812e97c42346e183b0bdcccdc8b13
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6031049
Commit-Queue: Noam Rosenthal nrosenthal@chromium.org
Reviewed-by: Annie Sullivan sullivan@chromium.org
Cr-Commit-Position: refs/heads/main@{#1384341}