Support backwards OfType

[ajcvickers]

For example:

var animals = context.Set<Kiwi>().OfType<Animal>().ToList();

Where Kiwi inherits from Animal. (Yes, I know this is pretty pointless...)

See test Can_use_backwards_of_type_animal.

Microsoft.EntityFrameworkCore.Query.InheritanceSqlServerTest.Can_use_backwards_of_type_animal

System.Collections.Generic.KeyNotFoundException : The given key 'Property: Eagle.Group (EagleGroup) Required' was not present in the dictionary.
   at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.VisitMethodCall(MethodCallExpression methodCallExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore.Relational\Query\RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.cs:line 77
   at System.Linq.Expressions.MethodCallExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitBinary(BinaryExpression node)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.VisitBinary(BinaryExpression binaryExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore.Relational\Query\RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.cs:line 64
   at System.Linq.Expressions.BinaryExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
   at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
   at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitUnary(UnaryExpression node)
   at System.Linq.Expressions.UnaryExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
   at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
   at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitConditional(ConditionalExpression node)
   at System.Linq.Expressions.ConditionalExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitConditional(ConditionalExpression node)
   at System.Linq.Expressions.ConditionalExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitBinary(BinaryExpression node)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.VisitBinary(BinaryExpression binaryExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore.Relational\Query\RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.cs:line 64
   at System.Linq.Expressions.BinaryExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
   at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
   at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitConditional(ConditionalExpression node)
   at System.Linq.Expressions.ConditionalExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitConditional(ConditionalExpression node)
   at System.Linq.Expressions.ConditionalExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
   at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
   at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitBinary(BinaryExpression node)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.VisitBinary(BinaryExpression binaryExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore.Relational\Query\RelationalShapedQueryCompilingExpressionVisitor.RelationalProjectionBindingRemovingExpressionVisitor.cs:line 64
   at System.Linq.Expressions.BinaryExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
   at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
   at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at System.Linq.Expressions.ExpressionVisitor.VisitLambda[T](Expression`1 node)
   at System.Linq.Expressions.Expression`1.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.VisitShapedQueryExpression(ShapedQueryExpression shapedQueryExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore.Relational\Query\RelationalShapedQueryCompilingExpressionVisitor.cs:line 52
   at Microsoft.EntityFrameworkCore.Query.ShapedQueryCompilingExpressionVisitor.VisitExtension(Expression extensionExpression) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\ShapedQueryCompilingExpressionVisitor.cs:line 72
   at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
   at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
   at Microsoft.EntityFrameworkCore.Query.QueryCompilationContext.CreateQueryExecutor[TResult](Expression query) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\QueryCompilationContext.cs:line 73
   at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](Expression query, Boolean async) in C:\aspnet\EntityFrameworkCore\src\EFCore\Storage\Database.cs:line 71
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](IDatabase database, Expression query, IModel model, Boolean async) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\QueryCompiler.cs:line 106
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass9_0`1.<Execute>b__0() in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\QueryCompiler.cs:line 96
   at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQueryCore[TFunc](Object cacheKey, Func`1 compiler) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\CompiledQueryCache.cs:line 84
   at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQuery[TResult](Object cacheKey, Func`1 compiler) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\CompiledQueryCache.cs:line 59
   at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\QueryCompiler.cs:line 92
   at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression) in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\EntityQueryProvider.cs:line 79
   at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable`1.GetEnumerator() in C:\aspnet\EntityFrameworkCore\src\EFCore\Query\Internal\EntityQueryable`.cs:line 94
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at Microsoft.EntityFrameworkCore.Query.InheritanceTestBase`1.Can_use_backwards_of_type_animal() in C:\aspnet\EntityFrameworkCore\test\EFCore.Specification.Tests\Query\InheritanceTestBase.cs:line 211

[ajcvickers]

Note from triage: ideally we will make this work. If not, we should consider throwing a better message, but be careful not to block cases that currently work (even if they only work when the database does not contain entities of a given type.) If we can't do a better message safely, and we can't make this work, then just close.