Grant origins engagement for having interactions on their notifications.

chrome/browser/engagement/site_engagement_service.cc

Index: chrome/browser/engagement/site_engagement_service.cc
diff --git a/chrome/browser/engagement/site_engagement_service.cc b/chrome/browser/engagement/site_engagement_service.cc
index edda88c4b38d468b73d20c7465cc203aec8c1342..132d9e1327800b20787220ff36866787e3621557 100644
--- a/chrome/browser/engagement/site_engagement_service.cc
+++ b/chrome/browser/engagement/site_engagement_service.cc
@@ -475,8 +475,9 @@ void SiteEngagementService::HandleMediaPlaying(
                            : SiteEngagementScore::GetVisibleMediaPoints());
 
   RecordMetrics();
+  double score = GetScore(url);
   for (SiteEngagementObserver& observer : observer_list_)
-    observer.OnEngagementIncreased(web_contents, url, GetScore(url));
+    observer.OnEngagementIncreased(web_contents, url, score);
 }
 
 void SiteEngagementService::HandleNavigation(content::WebContents* web_contents,
@@ -490,8 +491,9 @@ void SiteEngagementService::HandleNavigation(content::WebContents* web_contents,
   AddPoints(url, SiteEngagementScore::GetNavigationPoints());
 
   RecordMetrics();
+  double score = GetScore(url);
   for (SiteEngagementObserver& observer : observer_list_)
-    observer.OnEngagementIncreased(web_contents, url, GetScore(url));
+    observer.OnEngagementIncreased(web_contents, url, score);
 }
 
 void SiteEngagementService::HandleUserInput(
@@ -505,8 +507,23 @@ void SiteEngagementService::HandleUserInput(
   AddPoints(url, SiteEngagementScore::GetUserInputPoints());
 
   RecordMetrics();
+  double score = GetScore(url);
+  for (SiteEngagementObserver& observer : observer_list_)
+    observer.OnEngagementIncreased(web_contents, url, score);
+}
+
+void SiteEngagementService::HandleNotificationInteraction(const GURL& url) {
+  if (!ShouldRecordEngagement(url))
+    return;
+
+  SiteEngagementMetrics::RecordEngagement(
+      SiteEngagementMetrics::ENGAGEMENT_NOTIFICATION_INTERACTION);
+  AddPoints(url, SiteEngagementScore::GetNotificationInteractionPoints());
+
+  RecordMetrics();
+  double score = GetScore(url);
   for (SiteEngagementObserver& observer : observer_list_)
-    observer.OnEngagementIncreased(web_contents, url, GetScore(url));
+    observer.OnEngagementIncreased(nullptr, url, score);

[Peter Beverloo, 2017/03/16 12:24:14]

nit: I'd annotate the `nullptr` with /* web_contents */

[dominickn, 2017/03/16 23:25:03]

Done.

 }
 
 void SiteEngagementService::SendLevelChangeToHelpers(