Make it easier to test OSR with %OptimizeOsr() runtime call.

test/mjsunit/regress-sync-optimized-lists.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: --allow-natives-syntax --block-concurrent-recompilation
 // Flags: --no-concurrent-osr
 
 function Ctor() {
   this.a = 1;
 }
 
 function get_closure() {
   return function add_field(obj, osr) {
     obj.c = 3;
     var x = 0;
-    if (osr) {
-      %OptimizeFunctionOnNextCall(add_field, "osr");
-    }
+    if (osr) %OptimizeOsr();
     for (var i = 0; i < 10; i++) {
       x = i + 1;
     }
     return x;
   }
 }
 
 var f1 = get_closure();
 f1(new Ctor(), false);
 f1(new Ctor(), false);
 
 %OptimizeFunctionOnNextCall(f1, "concurrent");
 
 // Kick off concurrent recompilation and OSR.
 var o = new Ctor();
 f1(o, true);
 assertOptimized(f1, "no sync");
 
 // Flush the optimizing compiler's queue.
 %NotifyContextDisposed();
 assertUnoptimized(f1, "no sync");
 
 // Trigger deopt.
 o.c = 2.2;
 
 var f2 = get_closure();
 f2(new Ctor(), true);