Add UMA metrics to the 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 "base/gtest_prod_util.h"
@@ skipping 39 matching lines @@
   // The SiteEngagementService does not take ownership of |clock|. It is the
   // responsibility of the caller to make sure |clock| outlives this
   // SiteEngagementScore.
   SiteEngagementScore(base::Clock* clock,
                       const base::DictionaryValue& score_dict);
   ~SiteEngagementScore();
 
   double Score() const;
   void AddPoints(double points);
 
+  // Returns true if the maximum number of points today has been added. Resets
+  // the number of points added today if the day has changed.
+  bool MaxPointsPerDayAdded();
+
   // Updates the content settings dictionary |score_dict| with the current score
   // fields. Returns true if |score_dict| changed, otherwise return false.
   bool UpdateScoreDict(base::DictionaryValue* score_dict);
 
  private:
   friend class SiteEngagementScoreTest;
 
   // This version of the constructor is used in unit tests.
   explicit SiteEngagementScore(base::Clock* clock);
 
@@ skipping 58 matching lines @@
 
   // Update the karma score of the origin matching |url| for time-on-site, based
   // on user input.
   void HandleUserInput(const GURL& url);
 
   // Overridden from SiteEngagementScoreProvider:
   double GetScore(const GURL& url) override;
   double GetTotalEngagementPoints() override;
 
  private:
+  // Adds the specified number of points to the given origin, respecting the
+  // maximum limits for the day and overall.

[calamity, 2015/09/25 07:08:33]

nit: This should be moved into the previous CL but don't worry about it if it's
too annoying.

[dominickn, 2015/09/28 03:34:50]

Done.

   void AddPoints(const GURL& url, double points);
 
+  // Returns the number of origins with maximum daily and total engagement
+  // respectively.
+  int OriginsWithMaxDailyEngagement();
+  int OriginsWithMaxEngagement();
+
+  // Logs the total number of origins stored by the site engagement service, and
+  // the total accumulated engagement score.
+  void RecordStartupUmaStats();
+
   Profile* profile_;
 
   // The clock used to vend times.
   base::DefaultClock clock_;
 
   DISALLOW_COPY_AND_ASSIGN(SiteEngagementService);
 };
 
 #endif  // CHROME_BROWSER_ENGAGEMENT_SITE_ENGAGEMENT_SERVICE_H_