Revert "Revert "Add missing unregistrations when a connection ends.""

This reverts commit 207ec8c2dd1927edb5332afcafacccebfd2ca210.

Yes, this is a revert of a revert...IOW, I'm putting the original change
back in.

Original change information:
[[
  Bug: 22410282
  Change-Id: Ic2698d9ae768e27a346f71c7b0cd99c9a490e801
]]

Change-Id: I796bdc35ff727a46b766056ad9b2a4aabead0814
1 file changed