gnucash unstable: Fix timezone constructor crash when zone file has no transitions.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/5af21dfa (commit)
	from  https://github.com/Gnucash/gnucash/commit/0026b108 (commit)



commit 5af21dfad816a2a41594c02512b1dfc97818f60a
Author: John Ralls <jralls at ceridwen.us>
Date:   Mon Dec 18 09:48:17 2017 -0800

    Fix timezone constructor crash when zone file has no transitions.



Summary of changes:
 libgnucash/engine/gnc-timezone.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)