Fixed the case of no levels
Fixed the case of no levels


Former-commit-id: 000e2c5e53642491e03c851d62b53dcf9295eef5 [formerly 56ddd92301f1c40018da63fdf1e597a350789bb1]
Former-commit-id: 430ad70eb85378f23b3eaf5b0ab3e78844a475f1
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine