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

test/mjsunit/regress/regress-379770.js

Index: test/mjsunit/regress/regress-379770.js
diff --git a/test/mjsunit/regress/regress-379770.js b/test/mjsunit/regress/regress-379770.js
index a6653c25912094b1393df1d088ab516b16efbe32..ab1b339f7d6f676a664e094bbad2d25af00fd7ea 100644
--- a/test/mjsunit/regress/regress-379770.js
+++ b/test/mjsunit/regress/regress-379770.js
@@ -6,9 +6,7 @@
 
 function foo(obj) {
   var counter = 1;
-  for (var i = 0; i < obj.length; i++) {
-    %OptimizeFunctionOnNextCall(foo, "osr");
-  }
+  for (var i = 0; i < obj.length; i++) %OptimizeOsr();
   counter += obj;
   return counter;
 }