[Durable] Updated Durable heuristic to use 'important sites'

chrome/browser/engagement/site_engagement_score.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 CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SCORE_H_
 #define CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SCORE_H_
 
 #include <array>
 #include <memory>
 
@@ skipping 140 matching lines @@
   void set_last_engagement_time(const base::Time& time) {
     last_engagement_time_ = time;
   }
 
  private:
   FRIEND_TEST_ALL_PREFIXES(SiteEngagementScoreTest, FirstDailyEngagementBonus);
   FRIEND_TEST_ALL_PREFIXES(SiteEngagementScoreTest, PartiallyEmptyDictionary);
   FRIEND_TEST_ALL_PREFIXES(SiteEngagementScoreTest, PopulatedDictionary);
   FRIEND_TEST_ALL_PREFIXES(SiteEngagementScoreTest, Reset);
   friend class ChromePluginServiceFilterTest;
+  friend class DurableStoragePermissionContextTest;
   friend class FlashPermissionBrowserTest;
   friend class ImportantSitesUtilTest;
   friend class SiteEngagementHelperTest;
   friend class SiteEngagementScoreTest;
   friend class SiteEngagementServiceTest;
 
   using ParamValues = std::array<std::pair<std::string, double>, MAX_VARIATION>;
 
   // Array holding the values corresponding to each item in Variation array.
   static ParamValues& GetParamValues();
@@ skipping 50 matching lines @@
   // The origin this score represents.
   GURL origin_;
 
   // The settings to write this score to when Commit() is called.
   HostContentSettingsMap* settings_map_;
 
   DISALLOW_COPY_AND_ASSIGN(SiteEngagementScore);
 };
 
 #endif  // CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SCORE_H_