Speeding up HLTCalo_L2CaloEMClusterMonitor
Following the work in !30218 (merged) by @ponyisi for HLTCalo_TopoCaloClusterMonitor, the same speed up technique based on cutmasks is applied to HLTCalo_L2CaloEMClusterMonitor.
Following the work in !30218 (merged) by @ponyisi for HLTCalo_TopoCaloClusterMonitor, the same speed up technique based on cutmasks is applied to HLTCalo_L2CaloEMClusterMonitor.