Update src/Neo/SmartContract/ApplicationEngine.cs

Author: Jimmy

src/Neo/SmartContract/ApplicationEngine.cs

@@ -286,6 +286,7 @@ private ExecutionContext CallContractInternal(ContractState contract, ContractMe
             if (NativeContract.Policy.IsBlocked(Snapshot, contract.Hash))
                 throw new InvalidOperationException($"The contract {contract.Hash} has been blocked.");
 
+            // ref. https://github.com/neo-project/neo/pull/3290
             ExecutionContext currentContext = CurrentContext;
             ExecutionContextState state = currentContext.GetState<ExecutionContextState>();
             if (method.Safe)