Merge "Disable eject button for StubVolumes" am: fef33579a6 am: e817b6d6e7 am: 2ab139414a am: aed1ec2ab8

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1914530

Change-Id: I9c24e936fbeed05c15c65ff3b5ca671431eab9f5