Add a ScopedFeatureList class for testing and start using it.

components/autofill/core/browser/autofill_manager_unittest.cc

 // Copyright 2013 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/autofill/core/browser/autofill_manager.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <memory>
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/format_macros.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_vector.h"
 #include "base/metrics/field_trial.h"
 #include "base/run_loop.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/histogram_tester.h"
+#include "base/test/scoped_feature_list.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "components/autofill/core/browser/autocomplete_history_manager.h"
 #include "components/autofill/core/browser/autofill_download_manager.h"
 #include "components/autofill/core/browser/autofill_experiments.h"
 #include "components/autofill/core/browser/autofill_profile.h"
 #include "components/autofill/core/browser/autofill_test_utils.h"
 #include "components/autofill/core/browser/credit_card.h"
 #include "components/autofill/core/browser/personal_data_manager.h"
@@ skipping 724 matching lines @@
     download_manager_ = new TestAutofillDownloadManager(
         autofill_driver_.get(), autofill_manager_.get());
     // AutofillManager takes ownership of |download_manager_|.
     autofill_manager_->set_download_manager(download_manager_);
     external_delegate_.reset(new TestAutofillExternalDelegate(
         autofill_manager_.get(),
         autofill_driver_.get()));
     autofill_manager_->SetExternalDelegate(external_delegate_.get());
 
     // Clear all the things.
-    base::FeatureList::ClearInstanceForTesting();
     variations::testing::ClearAllVariationParams();
   }
 
   void TearDown() override {
     // Order of destruction is important as AutofillManager relies on
     // PersonalDataManager to be around when it gets destroyed.
     autofill_manager_.reset();
     autofill_driver_.reset();
 
     // Remove the AutofillWebDataService so TestPersonalDataManager does not
@@ skipping 14 matching lines @@
     params[kCreditCardSigninPromoImpressionLimitParamKey] =
         base::IntToString(impression_limit);
     ASSERT_TRUE(
         variations::AssociateVariationParams(kTrialName, kGroupName, params));
 
     // Enable the feature.
     std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
     feature_list->RegisterFieldTrialOverride(
         kAutofillCreditCardSigninPromo.name,
         base::FeatureList::OVERRIDE_ENABLE_FEATURE, trial.get());
-    base::FeatureList::SetInstance(std::move(feature_list));
+    scoped_feature_list_.InitWithFeatureList(std::move(feature_list));
 
     // Double-checking our params made it.
     std::map<std::string, std::string> actualParams;
     EXPECT_TRUE(variations::GetVariationParamsByFeature(
         kAutofillCreditCardSigninPromo, &actualParams));
     EXPECT_EQ(params, actualParams);
   }
 
   void GetAutofillSuggestions(int query_id,
                               const FormData& form,
@@ skipping 176 matching lines @@
   base::MessageLoop message_loop_;
   MockAutofillClient autofill_client_;
   std::unique_ptr<MockAutofillDriver> autofill_driver_;
   std::unique_ptr<TestAutofillManager> autofill_manager_;
   std::unique_ptr<TestAutofillExternalDelegate> external_delegate_;
   scoped_refptr<net::TestURLRequestContextGetter> request_context_;
   TestPaymentsClient* payments_client_;
   TestAutofillDownloadManager* download_manager_;
   TestPersonalDataManager personal_data_;
   base::FieldTrialList field_trial_list_;
+  base::test::ScopedFeatureList scoped_feature_list_;
 };
 
 class TestFormStructure : public FormStructure {
  public:
   explicit TestFormStructure(const FormData& form)
       : FormStructure(form) {}
   ~TestFormStructure() override {}
 
   void SetFieldTypes(const std::vector<ServerFieldType>& heuristic_types,
                      const std::vector<ServerFieldType>& server_types) {
@@ skipping 4199 matching lines @@
   FormsSeen(mixed_forms);
 
   // Suggestions should always be displayed.
   for (const FormFieldData& field : mixed_form.fields) {
     GetAutofillSuggestions(mixed_form, field);
     EXPECT_TRUE(external_delegate_->on_suggestions_returned_seen());
   }
 }
 
 }  // namespace autofill