Reset Context on invalid gaslimit (#260)

* add reset

* add to constructor

packages/contracts/contracts/optimistic-ethereum/OVM/execution/OVM_ExecutionManager.sol

@@ -85,6 +85,7 @@ contract OVM_ExecutionManager is iOVM_ExecutionManager, Lib_AddressResolver {
         ovmSafetyChecker = iOVM_SafetyChecker(resolve("OVM_SafetyChecker"));
         gasMeterConfig = _gasMeterConfig;
         globalContext = _globalContext;
+        _resetContext();
     }
 
 
@@ -183,6 +184,7 @@ contract OVM_ExecutionManager is iOVM_ExecutionManager, Lib_AddressResolver {
         // Make sure the transaction's gas limit is valid. We don't revert here because we reserve
         // reverts for INVALID_STATE_ACCESS.
         if (_isValidGasLimit(_transaction.gasLimit, _transaction.l1QueueOrigin) == false) {
+            _resetContext();
             return;
         }