capture_game: Focus navigation in the game capture session

Revise the focus navigation while in a game capture session.

Fixed: b/281100234
Change-Id: Ifbca87b6872b527007b2b9070f4cde6cd0a9d2da
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4559905


Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Min Chen <minch@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1149229}