[Password Manager Cleanup] Replaces NULL -> nullptr.

components/password_manager/core/browser/affiliation_utils_unittest.cc

 // Copyright 2014 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 "components/password_manager/core/browser/affiliation_utils.h"
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "components/password_manager/core/common/password_manager_switches.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 206 matching lines @@
       {"Enabled", "", true},
       {"Enabled", switches::kDisableAffiliationBasedMatching, false},
       {"Enabled", switches::kEnableAffiliationBasedMatching, true}};
 
   for (const auto& test_case : kTestCases) {
     SCOPED_TRACE(testing::Message("Command line = ")
                  << test_case.command_line_switch);
     SCOPED_TRACE(testing::Message("Group name = ")
                  << test_case.field_trial_group);
 
-    base::FieldTrialList field_trials(NULL);
+    base::FieldTrialList field_trials(nullptr);
     base::FieldTrialList::CreateFieldTrial(kFieldTrialName,
                                            test_case.field_trial_group);
 
     base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
     command_line.AppendSwitch(test_case.command_line_switch);
     EXPECT_EQ(test_case.expected_enabled,
               IsAffiliationBasedMatchingEnabled(command_line));
   }
 }
 
 }  // namespace password_manager