Clean up TestFeaturesNativeHandler to use the ExtensionsClient's JSON feature sources.

extensions/common/features/feature_provider.h

 // 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.
 
 #ifndef EXTENSIONS_COMMON_FEATURES_FEATURE_PROVIDER_H_
 #define EXTENSIONS_COMMON_FEATURES_FEATURE_PROVIDER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 13 matching lines @@
   // Returns the parent feature of |feature|, or NULL if there isn't one.
   virtual Feature* GetParent(Feature* feature) const = 0;
 
   // Returns the features inside the |parent| namespace, recursively.
   virtual std::vector<Feature*> GetChildren(const Feature& parent) const = 0;
 
   // Returns all features described by this instance, in asciibetical order.
   virtual const std::vector<std::string>& GetAllFeatureNames() const = 0;
 
   // Gets a feature provider for a specific feature type, like "permission".
-  static FeatureProvider* GetByName(const std::string& name);
+  static const FeatureProvider* GetByName(const std::string& name);
 
   // Directly access the common feature types.
-  static FeatureProvider* GetAPIFeatures();
-  static FeatureProvider* GetManifestFeatures();
-  static FeatureProvider* GetPermissionFeatures();
+  static const FeatureProvider* GetAPIFeatures();
+  static const FeatureProvider* GetManifestFeatures();
+  static const FeatureProvider* GetPermissionFeatures();
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_FEATURES_FEATURE_PROVIDER_H_