Improve permission persistence tests.

chrome/browser/permissions/permission_context_base_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 "chrome/browser/permissions/permission_context_base.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/macros.h"
 #include "base/metrics/field_trial.h"
 #include "base/test/histogram_tester.h"
 #include "base/test/mock_entropy_provider.h"
+#include "base/test/scoped_feature_list.h"
 #include "build/build_config.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "chrome/browser/infobars/infobar_service.h"
 #include "chrome/browser/permissions/permission_decision_auto_blocker.h"
 #include "chrome/browser/permissions/permission_queue_controller.h"
 #include "chrome/browser/permissions/permission_request_id.h"
 #include "chrome/browser/permissions/permission_util.h"
 #include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
@@ skipping 268 matching lines @@
       EXPECT_EQ(CONTENT_SETTING_ASK,
                 permission_context.GetContentSettingFromMap(url, url));
     }
 
     // Flush the dismissal counts. Enable the block on too many dismissals
     // feature, which is disabled by default.
     HostContentSettingsMapFactory::GetForProfile(profile())
         ->ClearSettingsForOneType(
             CONTENT_SETTINGS_TYPE_PROMPT_NO_DECISION_COUNT);
 
-    // Set up the custom parameter.
-    base::FieldTrialList field_trials_(nullptr);
-    base::FieldTrial* trial = base::FieldTrialList::CreateFieldTrial(
-        kPromptTrialName, kPromptGroupName);
-    base::FeatureList::ClearInstanceForTesting();
-    std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
-    feature_list->RegisterFieldTrialOverride(
-        features::kBlockPromptsIfDismissedOften.name,
-        base::FeatureList::OVERRIDE_ENABLE_FEATURE, trial);
-    base::FeatureList::SetInstance(std::move(feature_list));
-    EXPECT_EQ(base::FeatureList::GetFieldTrial(
-                  features::kBlockPromptsIfDismissedOften),
-              trial);
+    base::test::ScopedFeatureList feature_list;
+    feature_list.InitAndEnableFeature(features::kBlockPromptsIfDismissedOften);
 
     EXPECT_TRUE(
         base::FeatureList::IsEnabled(features::kBlockPromptsIfDismissedOften));
 
     // Sanity check independence per permission type by checking two of them.
     DismissMultipleTimesAndExpectBlock(url,
                                        content::PermissionType::GEOLOCATION,
                                        CONTENT_SETTINGS_TYPE_GEOLOCATION, 3);
     DismissMultipleTimesAndExpectBlock(url,
                                        content::PermissionType::NOTIFICATIONS,
                                        CONTENT_SETTINGS_TYPE_NOTIFICATIONS, 3);
-    base::FeatureList::ClearInstanceForTesting();
   }
 
   void TestVariationBlockOnSeveralDismissals_TestContent() {
     GURL url("https://www.google.com");
     NavigateAndCommit(url);
     base::HistogramTester histograms;
 
     // Set up the custom parameter and custom value.
     base::FieldTrialList field_trials_(nullptr);
     base::FieldTrial* trial = base::FieldTrialList::CreateFieldTrial(
@@ skipping 326 matching lines @@
   TestParallelRequests(CONTENT_SETTING_ALLOW);
 }
 
 TEST_F(PermissionContextBaseTests, TestParallelRequestsBlocked) {
   TestParallelRequests(CONTENT_SETTING_BLOCK);
 }
 
 TEST_F(PermissionContextBaseTests, TestParallelRequestsDismissed) {
   TestParallelRequests(CONTENT_SETTING_ASK);
 }