Crash on any entry of drum notes

Ubuntu Studio 14.04, GIT commit: 396c44f

1) nerw score for drums
2) click first measure
3) press N

Result: crash

Crash is here:

https://github.com/musescore/MuseScore/commit/6bbcfb55e5edf9b4377f06029…

Logical fix would seem to be to protect this line with "if (chord())".