added assertion to check for the existance of the hc
added assertion to check for the existance of the hc


Former-commit-id: b243315921f0c53bbc21936f57c7be84e0ac5e1b [formerly 219729a8abe421ddb71389b44bc3de2a055693a5] [formerly 219729a8abe421ddb71389b44bc3de2a055693a5 [formerly 3c207bb5597de8dd0180ebced50eb87ff1556a05]]
Former-commit-id: 67eeb237f1edb6d893393b7b58b778e897ebd200
Former-commit-id: d539c8ac1ea874f459b5439ee26efd2436aadbcb
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine