Add a ScopedFeatureList class for testing and start using it.

components/autofill/core/browser/autofill_assistant_unittest.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 "components/autofill/core/browser/autofill_assistant.h"
 
 #include <memory>
 
 #include "base/callback.h"
 #include "base/feature_list.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/scoped_feature_list.h"
 #include "components/autofill/core/browser/autofill_driver.h"
 #include "components/autofill/core/browser/autofill_experiments.h"
 #include "components/autofill/core/browser/autofill_manager.h"
 #include "components/autofill/core/browser/autofill_test_utils.h"
 #include "components/autofill/core/browser/credit_card.h"
 #include "components/autofill/core/browser/form_structure.h"
 #include "components/autofill/core/browser/test_autofill_client.h"
 #include "components/autofill/core/browser/test_autofill_driver.h"
 #include "components/autofill/core/common/autofill_constants.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ skipping 28 matching lines @@
 class AutofillAssistantTest : public testing::Test {
  protected:
   AutofillAssistantTest()
       : message_loop_(),
         autofill_client_(),
         autofill_driver_(),
         autofill_manager_(&autofill_driver_, &autofill_client_),
         autofill_assistant_(&autofill_manager_) {}
 
   void EnableAutofillCreditCardAssist() {
-    base::FeatureList::ClearInstanceForTesting();
-    std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
-    feature_list->InitializeFromCommandLine(kAutofillCreditCardAssist.name,
-                                            std::string());
-    base::FeatureList::SetInstance(std::move(feature_list));
+    scoped_feature_list_.InitAndEnableFeature(kAutofillCreditCardAssist);
   }
 
   // Returns an initialized FormStructure with credit card form data. To be
   // owned by the caller.
   std::unique_ptr<FormStructure> CreateValidCreditCardForm() {
     std::unique_ptr<FormStructure> form_structure;
     FormData form;
 
     FormFieldData field;
     field.form_control_type = "text";
@@ skipping 22 matching lines @@
     form_structure->DetermineHeuristicTypes();
 
     return form_structure;
   }
 
   base::MessageLoop message_loop_;
   TestAutofillClient autofill_client_;
   testing::NiceMock<TestAutofillDriver> autofill_driver_;
   MockAutofillManager autofill_manager_;
   AutofillAssistant autofill_assistant_;
+  base::test::ScopedFeatureList scoped_feature_list_;
 };
 
 MATCHER_P(CreditCardMatches, guid, "") {
   return arg.guid() == guid;
 }
 
 // If the feature is turned off, CanShowCreditCardAssist() always returns
 // false.
 TEST_F(AutofillAssistantTest, CanShowCreditCardAssist_FeatureOff) {
   std::unique_ptr<FormStructure> form_structure = CreateValidCreditCardForm();
@@ skipping 32 matching lines @@
   // prompt.
   EXPECT_CALL(
       autofill_manager_,
       FillCreditCardForm(kNoQueryId, _, _, CreditCardMatches(card.guid()),
                          /* empty cvc */ base::string16()));
 
   autofill_assistant_.ShowAssistForCreditCard(card);
 }
 
 }  // namespace autofill