merge_pr_48997

Add interactivity:inert focus() test

Test that focus() does not work for input in interactivity:inert. Also
test that flipping back to interactivity:auto in an inert subtree allows
focusing again.

Also modified test not tentative and still referring to visibility.

Bug: 370065759
Change-Id: I0a7d592f85566e550ef04028e7e0d734c831166a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5993677
Reviewed-by: Daniil Sakhapov [email protected]
Commit-Queue: Rune Lillesveen [email protected]
Cr-Commit-Position: refs/heads/main@{#1378872}