The sound panel and media panel are using the same window, so when it
transit from the sound panel to media panel, no window-change event will
be sent. Therefore, Talkback won't be able to re-focus the panel header
which lead to the lack of the announcement.
Fix this by adding setAccessibilityPanelTitle() to trigger Talkback.
Fixes: 140459762
Test: rebuild and test talkback on the media output panel.
Change-Id: I1442434315374dbbfe1d47ca8638180577c93168