Remove --harmony-async-await runtime flag

test/mjsunit/es8/async-arrow-lexical-this.js

Index: test/mjsunit/es8/async-arrow-lexical-this.js
diff --git a/test/mjsunit/harmony/async-arrow-lexical-this.js b/test/mjsunit/es8/async-arrow-lexical-this.js
similarity index 95%
rename from test/mjsunit/harmony/async-arrow-lexical-this.js
rename to test/mjsunit/es8/async-arrow-lexical-this.js
index 182db47a22bf31871a47c758e402634e82a5960f..38bdddc2c7b67f08b14e82bf9eeebd8ee8d24ed3 100644
--- a/test/mjsunit/harmony/async-arrow-lexical-this.js
+++ b/test/mjsunit/es8/async-arrow-lexical-this.js
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-async-await --allow-natives-syntax
+// Flags: --allow-natives-syntax
 
 function assertEqualsAsync(expected, run, msg) {
   var actual;