[automerger skipped] Merge "Revert "Move IMS to a listener type model instead of a poll model"" am: 0ad2adeb48 am: ff98cd706b am: 36097789ba am: a5833e3316 am: a7adadecc4 -s ours

am skip reason: Change-Id I182b03f32c1472a351c18e6cd2d0c1af146c4a39 with SHA-1 f07814e28e is in history

Original change: https://android-review.googlesource.com/c/platform/packages/services/Telephony/+/1443077

Change-Id: I66a21f75648ac61beeab7accf00f47ac915b3b1d