Fix accidental bug in yield* desugaring.

test/mjsunit/harmony/generators.js

Index: test/mjsunit/harmony/generators.js
diff --git a/test/mjsunit/harmony/generators.js b/test/mjsunit/harmony/generators.js
index 5b045049e9963c1d31bf15584544d6906f3b3a31..df6cec892532b83d37601f639ccda8aed6188d12 100644
--- a/test/mjsunit/harmony/generators.js
+++ b/test/mjsunit/harmony/generators.js
@@ -237,8 +237,8 @@
     let x = g();
     assertEquals({value: 1, done: false}, x.next());
     assertEquals({value: 42, done: false}, x.next());
-    assertEquals({value: 43, done: false}, x.return(666));
-    assertEquals({value: undefined, done: false}, x.next());
+    assertEquals({value: 43, done: false}, x.return(44));
+    assertEquals({value: 44, done: false}, x.next());
     assertEquals({value: undefined, done: true}, x.next());
   }
 
@@ -250,3 +250,23 @@
     assertThrowsEquals(() => x.next(), 666);
   }
 }
+
+
+{ // yield*, .return argument is final result
+
+  function* inner() {
+    yield 2;
+  }
+
+  function* g() {
+    yield 1;
+    return yield* inner();
+  }
+
+  {
+    let x = g();
+    assertEquals({value: 1, done: false}, x.next());
+    assertEquals({value: 2, done: false}, x.next());
+    assertEquals({value: 42, done: true}, x.return(42));
+  }
+}