Remove unnecessary immutable object creation

Author: SergeiPavlov

Orm/Xtensive.Orm/Orm/Linq/Translator.Materialization.cs

@@ -107,10 +107,6 @@ private static ProjectionExpression PrepareCachedQuery(
     private Materializer
       BuildMaterializer(ProjectionExpression projection, IEnumerable<Parameter<Tuple>> tupleParameters)
     {
-      var tupleReader = Expression.Parameter(typeof (RecordSetReader), "tupleReader");
-      var session = Expression.Parameter(typeof (Session), "session");
-      var parameterContext = Expression.Parameter(WellKnownOrmTypes.ParameterContext, "parameterContext");
-
       var itemProjector = projection.ItemProjector;
       var materializationInfo = itemProjector.Materialize(context, tupleParameters);
       var elementType = itemProjector.Item.Type;