Merge "AudioPolicy: manager: force gain on startSource when using HW Gain" am: ae1df9155c am: be7cabc2e0 am: a818367360 am: ac71d9d2e5

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/1296441

Change-Id: Idecc8411630198ae3ba5dddf73a4f952c7731dbc