Disable non-standard Promise functions in staging

test/mjsunit/es6/debug-promises/throw-with-undefined-reject.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --expose-debug-as debug --allow-natives-syntax
+// Flags: --expose-debug-as debug --allow-natives-syntax --promise-extra
 
 // Test debug events when an exception is thrown inside a Promise, which is
 // caught by a custom promise, which has no reject handler.
 // We expect two Exception debug events:
 //  1) when the exception is thrown in the promise q.
 //  2) when calling the undefined custom reject closure in MyPromise throws.
 
 Debug = debug.Debug;
 
 var expected_events = 2;
@@ skipping 60 matching lines @@
       }
     } catch (e) {
       %AbortJS(e + "\n" + e.stack);
     }
   }
 
   %EnqueueMicrotask(checkResult);
 }
 
 testDone(0);