Media Engagement: Add a UKM bit if the session changed isHigh

This adds an Engagement.IsHigh.Changed bit to the SessionFinished UKM
that will be true if the IsHigh bit changed during the lifetime of the
session.

BUG=814351

Change-Id: I48b296301a59d7f92ce6fd8ac7750c41ed2bbecd
Reviewed-on: https://chromium-review.googlesource.com/964181
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549242}

chrome/browser/media/media_engagement_score.h

@@ -108,6 +108,7 @@ class MediaEngagementScore final {
  protected:
   friend class MediaEngagementAutoplayBrowserTest;
   friend class MediaEngagementContentsObserverTest;
+  friend class MediaEngagementSessionTest;
   friend class MediaEngagementService;
 
   // Only used by the Media Engagement service when bulk loading data.

chrome/browser/media/media_engagement_session.cc

@@ -144,6 +144,7 @@ void MediaEngagementSession::RecordUkmMetrics() {
       .SetEngagement_Score(round(score.actual_score() * 100))
       .SetPlaybacks_Delta(significant_playback_recorded_)
       .SetEngagement_IsHigh(score.high_score())
+      .SetEngagement_IsHigh_Changed(high_score_changed_)
       .SetEngagement_IsHigh_Changes(score.high_score_changes())
       .SetEngagement_IsPreloaded(is_preloaded)
       .SetPlayer_Audible_Delta(audible_players_total_)
@@ -181,6 +182,7 @@ void MediaEngagementSession::CommitPendingData() {
 
   MediaEngagementScore score =
       service_->CreateEngagementScore(origin_.GetURL());
+  bool previous_high_value = score.high_score();
 
   if (pending_data_to_commit_.visit)
     score.IncrementVisits();
@@ -216,6 +218,9 @@ void MediaEngagementSession::CommitPendingData() {
 
   score.Commit();
 
+  // If the high state has changed store that in a bool.
+  high_score_changed_ = previous_high_value != score.high_score();
+
   pending_data_to_commit_.visit = pending_data_to_commit_.playback =
       pending_data_to_commit_.players = false;
 }

chrome/browser/media/media_engagement_session.h

@@ -107,6 +107,9 @@ class MediaEngagementSession : public base::RefCounted<MediaEngagementSession> {
   // Whether the session was restored.
   RestoreType restore_status_ = RestoreType::kNotRestored;
 
+  // If the |is_high_| bit has changed since this object was created.
+  bool high_score_changed_ = false;
+
   DISALLOW_COPY_AND_ASSIGN(MediaEngagementSession);
 };
 

chrome/browser/media/media_engagement_session_unittest.cc

@@ -114,6 +114,18 @@ class MediaEngagementSessionTest : public testing::Test {
 
   base::SimpleTestClock* test_clock() { return &test_clock_; }
 
+  void SetVisitsAndPlaybacks(int visits, int media_playbacks) {
+    MediaEngagementScore score =
+        service()->CreateEngagementScore(origin().GetURL());
+    score.SetVisits(visits);
+    score.SetMediaPlaybacks(media_playbacks);
+    score.Commit();
+  }
+
+  bool ScoreIsHigh() const {
+    return service()->HasHighEngagement(origin().GetURL());
+  }
+
  private:
   const url::Origin origin_;
   base::SimpleTestClock test_clock_;
@@ -567,6 +579,8 @@ TEST_F(MediaEngagementSessionTest, RecordUkmMetrics) {
                      ukm_entry, Entry::kPlaybacks_SecondsSinceLastName));
     EXPECT_EQ(0, *test_ukm_recorder().GetEntryMetric(
                      ukm_entry, Entry::kEngagement_IsHigh_ChangesName));
+    EXPECT_EQ(0, *test_ukm_recorder().GetEntryMetric(
+                     ukm_entry, Entry::kEngagement_IsHigh_ChangedName));
   }
 
   SetSignificantPlaybackRecordedForSession(session.get(), false);
@@ -602,6 +616,67 @@ TEST_F(MediaEngagementSessionTest, RecordUkmMetrics) {
                      ukm_entry, Entry::kPlaybacks_SecondsSinceLastName));
     EXPECT_EQ(0, *test_ukm_recorder().GetEntryMetric(
                      ukm_entry, Entry::kEngagement_IsHigh_ChangesName));
+    EXPECT_EQ(0, *test_ukm_recorder().GetEntryMetric(
+                     ukm_entry, Entry::kEngagement_IsHigh_ChangedName));
+  }
+}
+
+TEST_F(MediaEngagementSessionTest, RecordUkmMetrics_Changed_NowHigh) {
+  const std::string url_string = origin().GetURL().spec();
+  using Entry = ukm::builders::Media_Engagement_SessionFinished;
+
+  // Set the visits and playbacks to just below the threshold so the next
+  // significant playback will result in the playback being high.
+  SetVisitsAndPlaybacks(19, 5);
+  EXPECT_FALSE(ScoreIsHigh());
+
+  scoped_refptr<MediaEngagementSession> session = new MediaEngagementSession(
+      service(), origin(), MediaEngagementSession::RestoreType::kNotRestored);
+
+  session->RecordSignificantPlayback();
+
+  EXPECT_EQ(0u, test_ukm_recorder().GetEntriesByName(Entry::kEntryName).size());
+
+  RecordUkmMetricsForSession(session.get());
+
+  {
+    auto ukm_entries = test_ukm_recorder().GetEntriesByName(Entry::kEntryName);
+    EXPECT_EQ(1u, ukm_entries.size());
+
+    auto* ukm_entry = ukm_entries[0];
+    test_ukm_recorder().ExpectEntrySourceHasUrl(ukm_entry, origin().GetURL());
+    EXPECT_EQ(1u, *test_ukm_recorder().GetEntryMetric(
+                      ukm_entry, Entry::kEngagement_IsHigh_ChangedName));
+  }
+}
+
+TEST_F(MediaEngagementSessionTest, RecordUkmMetrics_Changed_WasHigh) {
+  const std::string url_string = origin().GetURL().spec();
+  using Entry = ukm::builders::Media_Engagement_SessionFinished;
+
+  // Set the visits and playbacks to just above the lower threshold and the is
+  // high bit to true so the next visit will cross the threshold.
+  SetVisitsAndPlaybacks(20, 20);
+  SetVisitsAndPlaybacks(20, 4);
+  EXPECT_TRUE(ScoreIsHigh());
+
+  scoped_refptr<MediaEngagementSession> session = new MediaEngagementSession(
+      service(), origin(), MediaEngagementSession::RestoreType::kNotRestored);
+
+  CommitPendingDataForSession(session.get());
+
+  EXPECT_EQ(0u, test_ukm_recorder().GetEntriesByName(Entry::kEntryName).size());
+
+  RecordUkmMetricsForSession(session.get());
+
+  {
+    auto ukm_entries = test_ukm_recorder().GetEntriesByName(Entry::kEntryName);
+    EXPECT_EQ(1u, ukm_entries.size());
+
+    auto* ukm_entry = ukm_entries[0];
+    test_ukm_recorder().ExpectEntrySourceHasUrl(ukm_entry, origin().GetURL());
+    EXPECT_EQ(1u, *test_ukm_recorder().GetEntryMetric(
+                      ukm_entry, Entry::kEngagement_IsHigh_ChangedName));
   }
 }
 

tools/metrics/ukm/ukm.xml

@@ -1099,18 +1099,87 @@ be describing additional metrics about the same event.
     media playbacks, the total number of visits, the calculated engagement score
     and the new number of significant media playbacks that occured this visit.
   </summary>
-  <metric name="Engagement.IsHigh"/>
-  <metric name="Engagement.IsHigh.Changes"/>
-  <metric name="Engagement.IsPreloaded"/>
-  <metric name="Engagement.Score"/>
-  <metric name="Playbacks.Delta"/>
-  <metric name="Playbacks.SecondsSinceLast"/>
-  <metric name="Playbacks.Total"/>
-  <metric name="Player.Audible.Delta"/>
-  <metric name="Player.Audible.Total"/>
-  <metric name="Player.Significant.Delta"/>
-  <metric name="Player.Significant.Total"/>
-  <metric name="Visits.Total"/>
+  <metric name="Engagement.IsHigh">
+    <summary>
+      Whether the Media Engagement Service considers the score to be high (we
+      are using a two threshold approach so there is one threshold to be
+      considered high and another one to lose that status to reduce jitter).
+    </summary>
+  </metric>
+  <metric name="Engagement.IsHigh.Changed">
+    <summary>
+      Whether the IsHigh bit changed during the current session.
+    </summary>
+  </metric>
+  <metric name="Engagement.IsHigh.Changes">
+    <summary>
+      Counts of IsHigh changing (from 0 to 1 or 1 to 0).
+    </summary>
+  </metric>
+  <metric name="Engagement.IsPreloaded">
+    <summary>
+      Whether the origin was preloaded (from the chrome://component) as a high
+      engagement origin.
+    </summary>
+  </metric>
+  <metric name="Engagement.Score">
+    <summary>
+      The calculated Media Engagement score for the current origin. The score is
+      calculated by dividing the number of significant media playbacks by the
+      number of visits. If the number of visits is below 5 then the score will
+      be zero. This score is taken from MediaEngagementService.
+    </summary>
+  </metric>
+  <metric name="Playbacks.Delta">
+    <summary>
+      The number of significant media playbacks on this origin during this
+      session (a visit to an origin on the same tab). A playback is determined
+      significant if it meets certain criteria such as a video size of at least
+      200x140px, is not muted, is playing, etc.
+    </summary>
+  </metric>
+  <metric name="Playbacks.SecondsSinceLast">
+    <summary>
+      The number of seconds between significant media playback on the last visit
+      and significant media playback on the current visit. If there was no
+      previous visit or significant media playback this visit it will be 0.
+    </summary>
+  </metric>
+  <metric name="Playbacks.Total">
+    <summary>
+      The total number of significant media playbacks on this origin.
+    </summary>
+  </metric>
+  <metric name="Player.Audible.Delta">
+    <summary>
+      The number of unique audio/video players on a page that was audible (made
+      sound) during a visit.
+    </summary>
+  </metric>
+  <metric name="Player.Audible.Total">
+    <summary>
+      The delta from above but instead of a single visit, the total of all
+      deltas for all visits on this origin.
+    </summary>
+  </metric>
+  <metric name="Player.Significant.Delta">
+    <summary>
+      The number of unique audio/video players on a page that was audible (made
+      sound) and considered significant (played for at least 7 seconds) during a
+      visit.
+    </summary>
+  </metric>
+  <metric name="Player.Significant.Total">
+    <summary>
+      The delta from above but instead of a single visit, the total of all
+      deltas for all visits on this origin.
+    </summary>
+  </metric>
+  <metric name="Visits.Total">
+    <summary>
+      The total number of visits to this origin.
+    </summary>
+  </metric>
 </event>
 
 <event name="Media.SiteMuted" singular="True">