moveBefore: fire focusout/focusin when moving focused element
If the moved element has focus within its tree, we fire focusout on
the old parent, and focusin on the new parent.
Note that this focusin might be fired on an inert subtree. We rely on
the focus fixup during the rendering step to correct the focus in this
event, which would fire a subsequent focusout on the previously focused
element, all the way up the tree.
Bug: 40150299
Change-Id: I6ce0c489bd498a4a56067253be2d9c0c32d38387
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5937967
Reviewed-by: Dominic Farolino dom@chromium.org
Commit-Queue: Noam Rosenthal nrosenthal@chromium.org
Cr-Commit-Position: refs/heads/main@{#1372142}