Remove --harmony-async-await runtime flag

test/mjsunit/es8/regress/regress-618603.js

Index: test/mjsunit/es8/regress/regress-618603.js
diff --git a/test/mjsunit/harmony/regress/regress-618603.js b/test/mjsunit/es8/regress/regress-618603.js
similarity index 91%
rename from test/mjsunit/harmony/regress/regress-618603.js
rename to test/mjsunit/es8/regress/regress-618603.js
index 8f45cd88f081fc4e601ec9b7dbe417c3be8476e3..2e6d4bd93959aabf868d4d0546aebd133229dc96 100644
--- a/test/mjsunit/harmony/regress/regress-618603.js
+++ b/test/mjsunit/es8/regress/regress-618603.js
@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-async-await
-
 try {
 } catch(e) {; }
 function __f_7(expected, run) {