commit 4b3b399c9532e9993708ff9d8b4b58249abece03
author Li Lin <llin@chromium.org> Mon Mar 18 17:21:05 2019
committer Commit Bot <commit-bot@chromium.org> Mon Mar 18 17:21:05 2019
tree b999d34e431fb74179703923eacd37a16d41d2d2
parent 15746b4f534f87218a44c5ad23122a28df6954d9

Handle audio focus for internal media player.

libassistant only request audio focus with
output type STREAM_MEDIA at the end of ReleaseFocusForStream.

We would like to request audio focus when the internal media player is
playing.

In this CL:
- When the internal media player start audio playback with audio output
type STREAM_MEDIA, we explicitly acquire audio focus.
- When the internal media player stop audio playback with audio output
type STREAM_MEDIA, we explicitly abandon audio focus if necessary.

Bug: b:123718677
Test: Manual
Change-Id: Ia30e685d7ed2186145140c38ae8526db5284a7ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1506554
Commit-Queue: Li Lin <llin@chromium.org>
Reviewed-by: Xiaohui Chen <xiaohuic@chromium.org>
Reviewed-by: Tao Wu <wutao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#641663}