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

test/mjsunit/regress/regress-crbug-506443.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 --crankshaft --no-always-opt
 
 assertSame = function assertSame() {
   if (found === expected) {
     if (1 / expected) return;
   } else if ((expected !== expected) && (found !== found)) {
     return;
   };
 };
 assertEquals = function assertEquals() {
   if (expected) {;
@@ skipping 64 matching lines @@
       var __v_2 = function() {
         a = 1;
       }
       Debug.setListener(__f_0);
       if (__v_0 < 2) Debug.setBreakPoint(__v_2);
     }
   })();
 } catch (e) {
   print();
 }