Fix return values for Harmony map and set operations.

test/mjsunit/harmony/collections.js

Index: test/mjsunit/harmony/collections.js
diff --git a/test/mjsunit/harmony/collections.js b/test/mjsunit/harmony/collections.js
index 412e6f14c32bd1d3b933fde22da22f3400241c5b..95504bc76ce9dfc94a4e434a029d63150bf69a4a 100644
--- a/test/mjsunit/harmony/collections.js
+++ b/test/mjsunit/harmony/collections.js
@@ -65,9 +65,11 @@ TestInvalidCalls(new WeakMap);
 // Test expected behavior for Sets
 function TestSet(set, key) {
   assertFalse(set.has(key));
-  set.add(key);
+  assertSame(undefined, set.add(key));
   assertTrue(set.has(key));
-  set.delete(key);
+  assertTrue(set.delete(key));
+  assertFalse(set.has(key));
+  assertFalse(set.delete(key));
   assertFalse(set.has(key));
 }
 function TestSetBehavior(set) {
@@ -87,7 +89,7 @@ TestSetBehavior(new Set);
 
 // Test expected mapping behavior for Maps and WeakMaps
 function TestMapping(map, key, value) {
-  map.set(key, value);
+  assertSame(undefined, map.set(key, value));
   assertSame(value, map.get(key));
 }
 function TestMapBehavior1(m) {