No naturals appear for change to open/atonal key signature
Ubuntu 14.04, GIT commit: 59250c6
1) new score, D major
2) drag open/atonal key signature to measure 3
Result: no visible evidence of the key change. Expected result is to see the cancelling naturals. Although the open/atonal key signature is implemented as a custom key and we normally suppress the naturals, we should special case this one (custom key with no symbols) if possible.