The maps of expat ids in SipTransactionPersistentManager and
ReplicatoinDialogFragmentManager are incorrectly synchronized. The goal was to
have a read/write lock on the theory that they are modified infrequently (during
shape change). But they are modified as the expat ids are removed from the map;
the removal however is incorrectly using the readlock.
It will not be sufficient to change that to the writelock, as then we will have
some unwanted cases where the readLock.try fails. We will need to modify the
pattern to get the desired semantics (write locked during calculation, but
thread safe otherwise).