Microsoft.CodeAnalysis.CSharp.Symbols.NamespaceSymbol.GetExtensionMembers(Microsoft.CodeAnalysis.PooledObjects.ArrayBuilder<Microsoft.CodeAnalysis.CSharp.Symbol>, System.String, System.String, System.Int32, Microsoft.CodeAnalysis.CSharp.LookupOptions, Roslyn.Utilities.ConsList<Microsoft.CodeAnalysis.CSharp.Symbols.FieldSymbol>)