Add support for yield expressions

test/mjsunit/harmony/generators-iteration.js

Index: test/mjsunit/harmony/generators-iteration.js
diff --git a/test/mjsunit/harmony/generators-iteration.js b/test/mjsunit/harmony/generators-iteration.js
index 09a4cc50d6472be689745f21bd6a63bd4fe07d70..b64d583b7b86a82a4e44fb224cf182e2c526a2a9 100644
--- a/test/mjsunit/harmony/generators-iteration.js
+++ b/test/mjsunit/harmony/generators-iteration.js
@@ -239,6 +239,32 @@ function TestReceivers() {
 // TestReceivers();
 
 TestGenerator(
+    function* g20() { yield (1 + (yield 2) + 3); },
+    [2, NaN, undefined],
+    "foo",
+    [2, "1foo3", undefined]);
+
+TestGenerator(
+    function* g21() { return (1 + (yield 2) + 3); },
+    [2, NaN],
+    "foo",
+    [2, "1foo3"]);
+
+TestGenerator(
+    function* g22() { yield (1 + (yield 2) + 3); yield (4 + (yield 5) + 6); },
+    [2, NaN, 5, NaN, undefined],
+    "foo",
+    [2, "1foo3", 5, "4foo6", undefined]);
+
+TestGenerator(
+    function* g23() {
+      return (yield (1 + (yield 2) + 3)) + (yield (4 + (yield 5) + 6));
+    },
+    [2, NaN, 5, NaN, NaN],
+    "foo",
+    [2, "1foo3", 5, "4foo6", "foofoo"]);
+
+TestGenerator(
     function* g() {
       var x = 1;
       yield x;