Revert of Change ScopedFeatureList to overrides FeatureList not reset

base/test/scoped_feature_list.h

 // 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.
 
 #ifndef BASE_TEST_SCOPED_FEATURE_LIST_H_
 #define BASE_TEST_SCOPED_FEATURE_LIST_H_
 
 #include <initializer_list>
 
 #include "base/feature_list.h"
 
 namespace base {
 namespace test {
 
 // ScopedFeatureList resets the global FeatureList instance to a new empty
 // instance and restores the original instance upon destruction.
 // Note: Re-using the same object is not allowed. To reset the feature
 // list and initialize it anew, destroy an existing scoped list and init
 // a new one.
 class ScopedFeatureList final {
  public:
   ScopedFeatureList();
   ~ScopedFeatureList();
 
-  // WARNING: This method will reset any globally configured features to their
-  // default values, which can hide feature interaction bugs. Please use
-  // sparingly.  https://crbug.com/713390
   // Initializes and registers a FeatureList instance with no overrides.
   void Init();
 
-  // WARNING: This method will reset any globally configured features to their
-  // default values, which can hide feature interaction bugs. Please use
-  // sparingly.  https://crbug.com/713390
   // Initializes and registers the given FeatureList instance.
   void InitWithFeatureList(std::unique_ptr<FeatureList> feature_list);
 
-  // WARNING: This method will reset any globally configured features to their
-  // default values, which can hide feature interaction bugs. Please use
-  // sparingly.  https://crbug.com/713390
-  // Initializes and registers a FeatureList instance with only the given
+  // Initializes and registers a FeatureList instance with the given enabled
+  // and disabled features.
+  void InitWithFeatures(
+      const std::initializer_list<base::Feature>& enabled_features,
+      const std::initializer_list<base::Feature>& disabled_features);
+
+  // Initializes and registers a FeatureList instance with the given
   // enabled and disabled features (comma-separated names).
   void InitFromCommandLine(const std::string& enable_features,
                            const std::string& disable_features);
 
-  // Initializes and registers a FeatureList instance based on present
-  // FeatureList and overridden with the given enabled and disabled features.
-  // Any feature overrides already present in the global FeatureList will
-  // continue to apply, unless they conflict with the overrides passed into this
-  // method. This is important for testing potentially unexpected feature
-  // interactions.
-  void InitWithFeatures(
-      const std::initializer_list<base::Feature>& enabled_features,
-      const std::initializer_list<base::Feature>& disabled_features);
-
-  // Initializes and registers a FeatureList instance based on present
-  // FeatureList and overridden with single enabled feature.
+  // Initializes and registers a FeatureList instance enabling a single
+  // feature.
   void InitAndEnableFeature(const base::Feature& feature);
 
-  // Initializes and registers a FeatureList instance based on present
-  // FeatureList and overridden with single disabled feature.
+  // Initializes and registers a FeatureList instance disabling a single
+  // feature.
   void InitAndDisableFeature(const base::Feature& feature);
 
  private:
   std::unique_ptr<FeatureList> original_feature_list_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedFeatureList);
 };
 
 }  // namespace test
 }  // namespace base
 
 #endif  // BASE_TEST_SCOPED_FEATURE_LIST_H_