Optimize functions containing try-catch.

tests/language/try_catch3_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // Dart test program for testing try/catch statement without any exceptions
 // being thrown.
 
 import "package:expect/expect.dart";
 
 abstract class TestException {
   String getMessage();
@@ skipping 95 matching lines @@
   }
 }
 
 class TryCatchTest {
   static testMain() {
     Expect.equals(900, Helper.test1(1));
   }
 }
 
 main() {
-  TryCatchTest.testMain();
+  for (var i = 0; i < 2000; i++) {
+    TryCatchTest.testMain();
+  }
 }