Merge pull request #23170 from TravCav/master

isDefaultExport is always false here.

src/compiler/binder.ts

@@ -399,7 +399,7 @@ namespace ts {
                                 // 1. multiple export default of class declaration or function declaration by checking NodeFlags.Default
                                 // 2. multiple export default of export assignment. This one doesn't have NodeFlags.Default on (as export default doesn't considered as modifiers)
                                 if (symbol.declarations && symbol.declarations.length &&
-                                    (isDefaultExport || (node.kind === SyntaxKind.ExportAssignment && !(<ExportAssignment>node).isExportEquals))) {
+                                    (node.kind === SyntaxKind.ExportAssignment && !(<ExportAssignment>node).isExportEquals)) {
                                     message = Diagnostics.A_module_cannot_have_multiple_default_exports;
                                 }
                             }