Use intermediate vars instead of complex expression in CreateLocalCollectionProjectionExpression()

Author: SergeiPavlov

Orm/Xtensive.Orm/Orm/Linq/Translator.Expressions.cs

@@ -1593,16 +1593,17 @@ private static Expression MakeBooleanExpression(Expression previous, Expression
     private static ProjectionExpression CreateLocalCollectionProjectionExpression(Type itemType, object value, Translator translator, Expression sourceExpression)
     {
       var storedEntityType = translator.State.TypeOfEntityStoredInKey;
-      var itemToTupleConverter = ItemToTupleConverter.BuildConverter(itemType, storedEntityType, value, translator.context.Model, sourceExpression);
+      var translatorContext = translator.context;
+      var itemToTupleConverter = ItemToTupleConverter.BuildConverter(itemType, storedEntityType, value, translatorContext.Model, sourceExpression);
       var tupleDescriptor = itemToTupleConverter.TupleDescriptor;
       var columns = tupleDescriptor
-        .Select(x => new SystemColumn(translator.context.GetNextColumnAlias(), 0, x))
+        .Select(x => new SystemColumn(translatorContext.GetNextColumnAlias(), 0, x))
         .Cast<Column>()
         .ToArray(tupleDescriptor.Count);
       var rsHeader = new RecordSetHeader(tupleDescriptor, columns);
       var rawProvider = new RawProvider(rsHeader, itemToTupleConverter.GetEnumerable());
       var recordset = new StoreProvider(rawProvider);
-      var itemProjector = new ItemProjectorExpression(itemToTupleConverter.Expression, recordset, translator.context);
+      var itemProjector = new ItemProjectorExpression(itemToTupleConverter.Expression, recordset, translatorContext);
       if (translator.State.JoinLocalCollectionEntity)
         itemProjector = EntityExpressionJoiner.JoinEntities(translator, itemProjector);
       return new ProjectionExpression(itemType, itemProjector, TranslatedQuery.EmptyTupleParameterBindings);