Merge "Add global microphone mute key for keyboard" am: e85f2710 am: 13e8df2c am: 34b40ae5

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2263102



Change-Id: I735e363e875dd6f4a8aca6bb2d01f83322865787
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>