[automerger skipped] Add the ability to return SipTransport implementation if...

[automerger skipped] Add the ability to return SipTransport implementation if capable am: 0eafb70e am: ac218451 am: 63a3c763 am: bd9324be -s ours

am skip reason: Change-Id Id72487917c804476f0e8f96e4ef9e98e48c5f237 with SHA-1 ba606d1f is in history

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/net/ims/+/1453735

Change-Id: I9aff2f33b916937868856edce0682a718f436d66