Fix Reflect.construct wrt proxy, generator, and non-subclass new.target

test/mjsunit/harmony/reflect-construct.js

Index: test/mjsunit/harmony/reflect-construct.js
diff --git a/test/mjsunit/harmony/reflect-construct.js b/test/mjsunit/harmony/reflect-construct.js
index 2211e3f7837a03e1e8fc0b48cf4f04c363044b58..8e43b19a34269e3687ad9bc7f43cf1bb5239e535 100644
--- a/test/mjsunit/harmony/reflect-construct.js
+++ b/test/mjsunit/harmony/reflect-construct.js
@@ -275,3 +275,12 @@
   assertEquals(10, Reflect.construct(sumSloppy,
                                      { 0: 1, 1: 2, 2: 3, 3: 4, length: 4 }).a);
 })();
+
+(function() {
+  function* f() { yield 1; yield 2; }
+  function* g() { yield 3; yield 4; }
+  var o = Reflect.construct(f, [], g);
+  assertEquals([1, 2], [...o]);
+  assertTrue(o.__proto__ === g.prototype);
+  assertTrue(o.__proto__ !== f.prototype);
+})();