4198: Person view does not remove a row correctly when two people are merged.

This patch improves on the context changes:
 * avoid use of transaction_xx methods
 * force an abort in case of unclean transaction

Backward compatibility is broken to achieve this.


svn: r16680

src/Merge/mergeevent.py

@@ -29,6 +29,7 @@ Provide merge capabilities for events.
 # Gramps modules
 #
 #-------------------------------------------------------------------------
+from gen.db import DbTxn
 from gen.ggettext import sgettext as _
 import const
 import GrampsDisplay