[runtime] [proxies] adding tests for uncovered branches

test/mjsunit/harmony/proxies-define-property.js

Index: test/mjsunit/harmony/proxies-define-property.js
diff --git a/test/mjsunit/harmony/proxies-define-property.js b/test/mjsunit/harmony/proxies-define-property.js
index f302db2621aa75e45c1533d2fd4169b2af9a1761..27f23be1734946a1355ad0614bae1d3376906215 100644
--- a/test/mjsunit/harmony/proxies-define-property.js
+++ b/test/mjsunit/harmony/proxies-define-property.js
@@ -23,7 +23,16 @@ assertSame(target, g_target);
 assertEquals("foo", g_name);
 assertEquals(desc, g_desc);
 
-// Check specific steps in the spec:
+// Check specific steps in the spec
+
+// Step 4: revoked handler
+var pair = Proxy.revocable(target, handler);
+Object.defineProperty(proxy, "foo2", desc);
+assertSame(target, g_target);
+assertEquals("foo2", g_name);
+assertEquals(desc, g_desc);
+pair.revoke();
+assertThrows('Object.defineProperty(pair.proxy, "bar", desc);', TypeError);
 
 // Step 6: Trap isn't callable.
 handler.defineProperty = 1;