Fix use of proxies as f.prototype properties.

test/mjsunit/harmony/proxies.js

Index: test/mjsunit/harmony/proxies.js
diff --git a/test/mjsunit/harmony/proxies.js b/test/mjsunit/harmony/proxies.js
index 50c8613b6390c15f15b1245b5e33a9f65fd46c4b..8d8f83996e255832168fa0c3c5a2d3f117888cb8 100644
--- a/test/mjsunit/harmony/proxies.js
+++ b/test/mjsunit/harmony/proxies.js
@@ -2257,3 +2257,22 @@ TestIsEnumerableThrow(Proxy.create({
     return function(k) { throw "myexn" }
   }
 }))
+
+
+
+// Constructor functions with proxy prototypes.
+
+function TestConstructorWithProxyPrototype() {
+  TestWithProxies(TestConstructorWithProxyPrototype2, {})
+}
+
+function TestConstructorWithProxyPrototype2(create, handler) {
+  function C() {};
+  C.prototype = create(handler);
+
+  var o = new C;
+  assertSame(C.prototype, o.__proto__);
+  assertSame(C.prototype, Object.getPrototypeOf(o));
+}
+
+TestConstructorWithProxyPrototype();