Merge "Integrate IMS single registration feature into APIs" am: a271c76c47

Original change: https://android-review.googlesource.com/c/platform/packages/services/Telephony/+/1564733

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I63df15ff0d2b0bc6bd6c65d6f6d6d14571fc25cd