Added test.

tests/cases/conformance/es6/modules/defaultExportsCannotMerge03.ts

@@ -0,0 +1,26 @@
+// @module: commonjs
+// @target: ES5
+
+// @filename: m1.ts
+export default class Decl {
+}
+
+interface Decl {
+    p1: number;
+    p2: number;
+}
+
+namespace Decl {
+    interface I {
+    }
+}
+
+// @filename: m2.ts
+import Entity from "m1"
+
+Entity();
+
+var x: Entity;
+var y: Entity.I;
+var z = new Entity();
+var sum = z.p1 + z.p2