Add a new function for getting a deterministic machine ID

chrome/browser/prefs/tracked/device_id_unittest.cc

+// Copyright 2015 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.
+
+#include "chrome/browser/prefs/tracked/device_id.h"
+#include "build/build_config.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+TEST(GetDeterministicMachineSpecificIdTest, IsDeterministic) {
+  std::string first_machine_id;
+  std::string second_machine_id;
+
+  const MachineIdStatus kExpectedStatus =
+#if defined(OS_WIN)
+      MachineIdStatus::SUCCESS;
+#else
+      MachineIdStatus::NOT_IMPLEMENTED;
+#endif
+
+  ASSERT_EQ(kExpectedStatus,
+            GetDeterministicMachineSpecificId(&first_machine_id));
+  ASSERT_EQ(kExpectedStatus,
+            GetDeterministicMachineSpecificId(&second_machine_id));
+
+  // The reason for using |EXPECT_TRUE| with one argument instead of |EXPECT_EQ|
+  // with two arguments is a compiler bug in gcc that results in a "converting
+  // 'false' to pointer type" error when the first argument to |EXPECT_EQ| is a
+  // compile-time const false value. See also the following bug reports:
+  // https://code.google.com/p/googletest/issues/detail?id=322
+  // https://code.google.com/p/googletest/issues/detail?id=458
+  EXPECT_TRUE((kExpectedStatus == MachineIdStatus::SUCCESS) ==
+              !first_machine_id.empty());
+  EXPECT_EQ(first_machine_id, second_machine_id);
+}