Fail tests fast if overriding the Windows registry fails.

chrome/browser/downgrade/user_data_downgrade_browsertest.cc

 // Copyright 2016 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/downgrade/user_data_downgrade.h"
 
 #include "base/files/file_util.h"
 #include "base/path_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/test_reg_util_win.h"
 #include "base/version.h"
 #include "base/win/registry.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/installer/util/browser_distribution.h"
 #include "chrome/installer/util/google_update_constants.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace downgrade {
 
 class UserDataDowngradeBrowserTestBase : public InProcessBrowserTest {
  protected:
   // content::BrowserTestBase:
   void SetUpInProcessBrowserTestFixture() override {
     HKEY root = HKEY_CURRENT_USER;
-    registry_override_manager_.OverrideRegistry(root);
+    ASSERT_NO_FATAL_FAILURE(registry_override_manager_.OverrideRegistry(root));
     key_.Create(root,
                 BrowserDistribution::GetDistribution()->GetStateKey().c_str(),
                 KEY_SET_VALUE | KEY_WOW64_32KEY);
   }
 
   // InProcessBrowserTest:
   bool SetUpUserDataDirectory() override {
     if (!PathService::Get(chrome::DIR_USER_DATA, &user_data_dir_))
       return false;
     if (!CreateTemporaryFileInDir(user_data_dir_, &other_file_))
@@ skipping 87 matching lines @@
   ASSERT_TRUE(base::PathExists(other_file_));
 }
 
 // Verify the "Last Version" file won't be created for non-msi install.
 IN_PROC_BROWSER_TEST_F(UserDataDowngradeBrowserNoMSITest, Test) {
   ASSERT_FALSE(base::PathExists(last_version_file_path_));
   ASSERT_TRUE(base::PathExists(other_file_));
 }
 
 }  // namespace downgrade