Query: compilation error (value does not fall within expected range) for query with order by, skip, another orderby and group aggregate

[maumar]

query:

                var query = ctx.Orders.OrderBy(o => o.OrderID)
                        .Skip(80)
                        .OrderBy(gg => gg.CustomerID)
                        .GroupBy(o => o.CustomerID)
                        .Select(g => g.Average(o => o.OrderID));

                var result = query.ToList();

query model (at the time of error):

from IGrouping<string, Order> g in 
    (from Order gg in 
        (from Order o in DbSet<Order>
        order by [o].OrderID asc
        select [o]).Skip(__p_0)
    order by [gg].CustomerID asc
    select [gg]).GroupBy([gg].CustomerID, [gg])
select 
    (from Order o in [g]
    select [o].OrderID).Average()

subquery that is being visited when exception happens:

(from Order o in [g]
select [o].OrderID).Average()

_expression is expected to be of a sequence type, but in fact it's typed as ValueBuffer

exception:

Value does not fall within the expected range.
	at System.SharedTypeExtensions.GetSequenceType(Type type)
	at Microsoft.EntityFrameworkCore.Query.EntityQueryModelVisitor.VisitMainFromClause(MainFromClause fromClause, QueryModel queryModel)
	at Remotion.Linq.Clauses.MainFromClause.Accept(IQueryModelVisitor visitor, QueryModel queryModel)
	at Remotion.Linq.QueryModelVisitorBase.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.EntityQueryModelVisitor.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.RelationalQueryModelVisitor.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.RelationalQueryModelVisitor.VisitSubQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.ExpressionVisitors.SqlTranslatingExpressionVisitor.VisitSubQuery(SubQueryExpression expression)
	at Remotion.Linq.Clauses.Expressions.SubQueryExpression.Accept(ExpressionVisitor visitor)
	at Remotion.Linq.Parsing.ThrowingExpressionVisitor.Visit(Expression expression)
	at Microsoft.EntityFrameworkCore.Query.ExpressionVisitors.SqlTranslatingExpressionVisitor.Visit(Expression expression)
	at Microsoft.EntityFrameworkCore.Query.ExpressionVisitors.RelationalProjectionExpressionVisitor.Visit(Expression expression)
	at Microsoft.EntityFrameworkCore.Query.EntityQueryModelVisitor.VisitSelectClause(SelectClause selectClause, QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.RelationalQueryModelVisitor.VisitSelectClause(SelectClause selectClause, QueryModel queryModel)
	at Remotion.Linq.Clauses.SelectClause.Accept(IQueryModelVisitor visitor, QueryModel queryModel)
	at Remotion.Linq.QueryModelVisitorBase.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.EntityQueryModelVisitor.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.RelationalQueryModelVisitor.VisitQueryModel(QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Query.EntityQueryModelVisitor.CreateQueryExecutor[TResult](QueryModel queryModel)
	at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](QueryModel queryModel)
	--- End of stack trace from previous location where exception was thrown ---
	at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
	at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](Expression query, IQueryModelGenerator queryModelGenerator, IDatabase database, IDiagnosticsLogger`1 logger, Type contextType)
	at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass13_0`1.<Execute>b__0()
	at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQueryCore[TFunc](Object cacheKey, Func`1 compiler)
	at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQuery[TResult](Object cacheKey, Func`1 compiler)
	at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query)
	at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression)
	at Remotion.Linq.QueryableBase`1.GetEnumerator()
	at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
	at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)

[smitpatel]

Dependent on #12089

[divega]

As per triage discussion, removing propose-punt label. IIRC, we said we believe this will be fixed for 3.0.