[tests] Cleanup tests that use assertOptimized()/assertUnoptimized().

test/mjsunit/regress/regress-4121.js

 // Copyright 2015 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: --allow-natives-syntax
+// Flags: --allow-natives-syntax --no-always-opt
 
 function literals_sharing_test(warmup, optimize) {
   function closure() {
     // Ensure small array literals start in specific element kind mode.
     assertTrue(%HasFastSmiElements([]));
     assertTrue(%HasFastSmiElements([1]));
     assertTrue(%HasFastSmiElements([1,2]));
     assertTrue(%HasFastDoubleElements([1.1]));
     assertTrue(%HasFastDoubleElements([1.1,2]));
 
@@ skipping 16 matching lines @@
   var warmup = true;
   for (var i = 0; i < 3; i++) {
     print("iter: " + i + ", warmup: "+ warmup);
     literals_sharing_test(warmup, false);
     warmup = false;
   }
   print("iter: " + i + ", opt: true");
   literals_sharing_test(warmup, true);
 }
 
-
-function stress_opt_test() {}
-stress_opt_test();
-if (%GetOptimizationStatus(stress_opt_test) == 2) {
-  // This test is not suitable for --always-opt mode.
-  test();
-}
+test();