Make the windows_version.h functions threadsafe by using a singleton.

sandbox/src/dep_test.cc

Index: sandbox/src/dep_test.cc
===================================================================
--- sandbox/src/dep_test.cc	(revision 80667)
+++ sandbox/src/dep_test.cc	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -12,32 +12,6 @@
 
 namespace {
 
-class DepTest : public testing::Test {
- public:
-  static bool IsTestCaseDisabled() {
-    OSVERSIONINFOEX version_info;
-    version_info.dwOSVersionInfoSize = sizeof version_info;
-    GetVersionEx(reinterpret_cast<OSVERSIONINFO*>(&version_info));
-
-    // Windows 2000 doesn't support DEP at all.
-    if (version_info.dwMajorVersion == 5 && version_info.dwMinorVersion == 0)
-      return true;
-
-    // Windows XP Service Pack 0 and 1 don't support DEP at all.
-    if (version_info.dwMajorVersion == 5 && version_info.dwMinorVersion == 1
-        && version_info.wServicePackMajor < 2)
-      return true;
-
-    // Bug 1212371 Vista SP0 DEP support is half-baked. Nobody seem to have
-    // noticed!
-    if (version_info.dwMajorVersion == 6 &&
-        version_info.wServicePackMajor == 0)
-      return true;
-
-    return false;
-  }
-};
-
 BYTE kReturnCode[] = {
   // ret
   0xC3,
@@ -167,7 +141,7 @@
 }  // namespace
 
 // This test is disabled. See bug 1275842
-TEST_F(DepTest, DISABLED_TestDepDisable) {
+TEST(DepTest, DISABLED_TestDepDisable) {
   TestRunner runner(JOB_UNPROTECTED, USER_INTERACTIVE, USER_INTERACTIVE);
 
   runner.SetTimeout(INFINITE);