Fix test Debug_BreakOnUnhandledException in checked mode

runtime/vm/debugger_api_impl_test.cc

 // 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.
 
 #include "include/dart_debugger_api.h"
 #include "include/dart_mirrors_api.h"
 #include "platform/assert.h"
 #include "vm/dart_api_impl.h"
 #include "vm/thread.h"
 #include "vm/unit_test.h"
@@ skipping 2022 matching lines @@
                                       Dart_Handle exception_object,
                                       Dart_StackTrace trace) {
   breakpoint_hit_counter++;
 }
 
 
 // Check that the debugger is not called when an exception is
 // caught by Dart code.
 TEST_CASE(Debug_BreakOnUnhandledException) {
   const char* kScriptChars =
-      "void main() {                   \n"
+      "main() {                        \n"
       "  try {                         \n"
       "    throw 'broccoli';           \n"
       "  } catch (e) {                 \n"
       "    return 'carrots';           \n"
       "  }                             \n"
       "  return 'zucchini';            \n"
       "}                               \n";
 
   LoadScript(kScriptChars);
   Dart_FinalizeLoading();
@@ skipping 251 matching lines @@
       " null, 3, 7, 1, 8, 6, 9, 10, 10, 11, 11, 13,"
       " null, 4, 13, 3, 14, 10,"
       " null, 5, 17, 5, 18, 9, 19, 12,"
       " null, 6, 21, 1,"
       " null, 8, 24, 1, 25, 5, 26, 6, 27, 8,"
       " null, 9, 29, 1]",
       tokens_cstr);
 }
 
 }  // namespace dart