Merge "Document emergency case for setAllowedNetworkTypeBitmap" am: e9fb347e0b am: fd6c4f5f5d am: e8615e0ec7 am: 837c5016f8

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1531900

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I85d535b9fc2fb9b1667b9d5c3cd9070543d2c953