Adding utility method to test the version of the OS.

base/ios/device_util_unittest.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <Foundation/Foundation.h>
 
 #include "base/ios/device_util.h"
+#include "base/ios/ios_util.h"
 #include "base/sys_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 
 namespace {
 // The behavior of most of these utility functions depends on what they are run
 // on, so there is not much to unittest them. The APIs are run to make sure they
 // don't choke. Additional checks are added for particular APIs when needed.
 
@@ skipping 22 matching lines @@
 TEST_F(DeviceUtilTest, GetDeviceIdentifier) {
   std::string default_id = ios::device_util::GetDeviceIdentifier(NULL);
   std::string other_id = ios::device_util::GetDeviceIdentifier("ForTest");
   EXPECT_NE(default_id, other_id);
 
   NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
   [defaults removeObjectForKey:@"ChromiumClientID"];
   [defaults synchronize];
 
   std::string new_default_id = ios::device_util::GetDeviceIdentifier(NULL);
-  EXPECT_NE(default_id, new_default_id);
+  if (base::ios::IsRunningOnIOS6OrLater())
+    EXPECT_EQ(default_id, new_default_id);
+  else
+    EXPECT_NE(default_id, new_default_id);
 }
 
 }  // namespace