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

chrome/browser/bookmarks/enhanced_bookmarks_features.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 "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
 
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/sha1.h"
@@ skipping 36 matching lines @@
 }
 
 bool IsEnhancedBookmarksExperimentEnabled() {
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(switches::kManualEnhancedBookmarks) ||
       command_line->HasSwitch(switches::kManualEnhancedBookmarksOptout)) {
     return true;
   }
 
   std::string ext_id = GetEnhancedBookmarksExtensionIdFromFinch();
-  extensions::FeatureProvider* feature_provider =
+  const extensions::FeatureProvider* feature_provider =
       extensions::FeatureProvider::GetPermissionFeatures();
   extensions::Feature* feature = feature_provider->GetFeature("metricsPrivate");
   return feature && feature->IsIdInWhitelist(ext_id);
 }
 
 bool IsEnableDomDistillerSet() {
   if (CommandLine::ForCurrentProcess()->
       HasSwitch(switches::kEnableDomDistiller)) {
     return true;
   }
@@ skipping 12 matching lines @@
   if (chrome_variations::GetVariationParamValue(
           kFieldTrialName, "enable-sync-articles") == "1")
     return true;
 
   return false;
 }
 
 std::string GetEnhancedBookmarksExtensionIdFromFinch() {
   return chrome_variations::GetVariationParamValue(kFieldTrialName, "id");
 }