Merge changes I48fd336d,I4527e24a,I9dbc0c4d,Ib81550b4,I7e118631

* changes:
  Move {get,set}AncestralSerialNumber() to Trampoline
  Move updateTransportAttributes() to Trampoline
  Move more transport operations to Trampoline
  Move some transport operations to Trampoline
  Move backup agent operations to Trampoline.