add more extern cases

Author: swannodette

src/test/externs/test.js

@@ -4,8 +4,20 @@
 var Foo = function() {};
 Foo.prototype.wozMethod = function() {
 };
-
 /**
  * @return {Foo}
  */
 var baz = function() {};
+/**
+ * @constructor
+ */
+Foo.Bar = function() {};
+/**
+ * @return {Foo.Boo}
+ */
+Foo.Bar.prototype.baz = function() {};
+/**
+ * @constructor
+ */
+Foo.Boo = function() {};
+Foo.Boo.prototype.woz = function() {};