replace faulty assertion

h2/src/main/org/h2/mvstore/tx/RollbackDecisionMaker.java

@@ -30,7 +30,9 @@ final class RollbackDecisionMaker extends MVMap.DecisionMaker<Object[]> {
     @Override
     public MVMap.Decision decide(Object[] existingValue, Object[] providedValue) {
         assert decision == null;
-        assert existingValue != null;
+        // normaly existingValue will always be there except of db initialization
+        // where some undo log enty was captured on disk but actual map entry was not
+        if (existingValue != null ) {
             VersionedValue valueToRestore = (VersionedValue) existingValue[2];
             long operationId;
             if (valueToRestore == null ||
@@ -45,6 +47,7 @@ final class RollbackDecisionMaker extends MVMap.DecisionMaker<Object[]> {
                     listener.onRollback(map, key, previousValue, valueToRestore);
                 }
             }
+        }
         decision = MVMap.Decision.REMOVE;
         return decision;
     }