Construct the site engagement helper with a site engagement service.

chrome/browser/engagement/site_engagement_service.h

 // Copyright 2015 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_SERVICE_H_
 #define CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_
 
 #include <map>
 #include <memory>
 #include <set>
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "chrome/browser/engagement/site_engagement_metrics.h"
 #include "components/history/core/browser/history_service_observer.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "ui/base/page_transition_types.h"
 
 namespace base {
 class DictionaryValue;
 class Clock;
 }
 
+namespace content {
+class WebContents;
+}
+
 namespace history {
 class HistoryService;
 }
 
 class GURL;
 class Profile;
 class SiteEngagementScore;
 
 class SiteEngagementScoreProvider {
  public:
@@ skipping 101 matching lines @@
 
   // Post startup tasks: cleaning up origins which have decayed to 0, and
   // logging UMA statistics.
   void AfterStartupTask();
   void CleanupEngagementScores();
   void RecordMetrics();
 
   // Returns the median engagement score of all recorded origins.
   double GetMedianEngagement(const std::map<GURL, double>& score_map) const;
 
-  // Update the engagement score of the origin matching |url| for media playing.
-  // The points awarded are discounted if the media is being played in a non-
-  // visible tab.
-  void HandleMediaPlaying(const GURL& url, bool is_hidden);
+  // Update the engagement score of the origin loaded in |web_contents| for
+  // media playing. The points awarded are discounted if the media is being
+  // played in a non-visible tab.
+  void HandleMediaPlaying(content::WebContents* web_contents, bool is_hidden);
 
-  // Update the engagement score of the origin matching |url| for navigation.
-  void HandleNavigation(const GURL& url, ui::PageTransition transition);
+  // Update the engagement score of the origin loaded in |web_contents| for
+  // navigation.
+  void HandleNavigation(content::WebContents* web_contents,
+                        ui::PageTransition transition);
 
-  // Update the engagement score of the origin matching |url| for time-on-site,
-  // based on user input.
-  void HandleUserInput(const GURL& url,
+  // Update the engagement score of the origin loaded in |web_contents| for
+  // time-on-site, based on user input.
+  void HandleUserInput(content::WebContents* web_contents,
                        SiteEngagementMetrics::EngagementType type);
 
   // Overridden from history::HistoryServiceObserver:
   void OnURLsDeleted(history::HistoryService* history_service,
                      bool all_history,
                      bool expired,
                      const history::URLRows& deleted_rows,
                      const std::set<GURL>& favicon_urls) override;
 
   // Returns the number of origins with maximum daily and total engagement
@@ skipping 20 matching lines @@
   // origin's engagement score after an hour has elapsed triggers the next
   // upload.
   base::Time last_metrics_time_;
 
   base::WeakPtrFactory<SiteEngagementService> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SiteEngagementService);
 };
 
 #endif  // CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_