Add additional logging to PersistentConnectionManager

Also addresses potential issue where if we receive onDisconnected before
we receive onConnected, we could end up retrying immediately instead of
waiting. This change introduces handling for this special case.

This change also updates PersistentConnectionManagerTest to kotlin and
multivalent, and adds new test cases to cover this potential edge case.

Bug: 330902851
Test: atest PersistentConnectionManagerTest
Flag: EXEMPT bugfix
Change-Id: I8c3eeff68f1c47c95a1f7de0767c66901f3562c0