chore: cherry-pick 275865e8c237 from chromium

[nornagon]

Mac: Target a11y actions on certain containers to focused or activedescendant children

When an action is triggered on a container with selectable children and
that container has a focused or activedescendant child, retarget the
action to that child. This fixes an issue where when the VoiceOver
cursor is on a tree with a focused child, triggered context menus would
use the tree as the target element.

menu on a tree instead of a focused child.

Bug: 1114892
Change-Id: Ibe580beed93aeaac54d1dabaee28443b290fd0e2
AX-Relnotes: Fix an issue where VoiceOver would trigger a context
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2466281
Commit-Queue: Martin Robinson mrobinson@igalia.com
Reviewed-by: Scott Violet sky@chromium.org
Reviewed-by: Dominic Mazzoni dmazzoni@chromium.org
Reviewed-by: Nektarios Paisios nektar@chromium.org
Cr-Commit-Position: refs/heads/master@{#818831}

Notes: Backported fix for https://crbug.com/1114892.

[jkleinsc]

Merging as CI failures are unrelated to PR change.

[release-clerk]

Release Notes Persisted

Backported fix for https://crbug.com/1114892.