Improve knowledge of last playing period in AnalyticsCollector.

We keep track of the last publicly known playing period to report it as part
of events happening after the period has been released.

In cases where a period briefly becomes the playing one and is released
immediately afterwards, we currently don't save it as the "last known playing
one". Improve that by saving an explicit reference.

Issue:#5407
PiperOrigin-RevId: 259737218

library/core/src/main/java/com/google/android/exoplayer2/MediaPeriodQueue.java

@@ -277,8 +277,8 @@ import com.google.android.exoplayer2.util.Assertions;
     if (front != null) {
     if (front != null) {
       oldFrontPeriodUid = keepFrontPeriodUid ? front.uid : null;
       oldFrontPeriodUid = keepFrontPeriodUid ? front.uid : null;
       oldFrontPeriodWindowSequenceNumber = front.info.id.windowSequenceNumber;
       oldFrontPeriodWindowSequenceNumber = front.info.id.windowSequenceNumber;
-      front.release();
       removeAfter(front);
       removeAfter(front);
+      front.release();
     } else if (!keepFrontPeriodUid) {
     } else if (!keepFrontPeriodUid) {
       oldFrontPeriodUid = null;
       oldFrontPeriodUid = null;
     }
     }

library/core/src/main/java/com/google/android/exoplayer2/analytics/AnalyticsCollector.java

@@ -686,6 +686,7 @@ public class AnalyticsCollector
     private final HashMap<MediaPeriodId, MediaPeriodInfo> mediaPeriodIdToInfo;
     private final HashMap<MediaPeriodId, MediaPeriodInfo> mediaPeriodIdToInfo;
     private final Period period;
     private final Period period;
 
 
+    @Nullable private MediaPeriodInfo lastPlayingMediaPeriod;
     @Nullable private MediaPeriodInfo lastReportedPlayingMediaPeriod;
     @Nullable private MediaPeriodInfo lastReportedPlayingMediaPeriod;
     @Nullable private MediaPeriodInfo readingMediaPeriod;
     @Nullable private MediaPeriodInfo readingMediaPeriod;
     private Timeline timeline;
     private Timeline timeline;
@@ -780,7 +781,7 @@ public class AnalyticsCollector
 
 
     /** Updates the queue with a reported position discontinuity . */
     /** Updates the queue with a reported position discontinuity . */
     public void onPositionDiscontinuity(@Player.DiscontinuityReason int reason) {
     public void onPositionDiscontinuity(@Player.DiscontinuityReason int reason) {
-      updateLastReportedPlayingMediaPeriod();
+      lastReportedPlayingMediaPeriod = lastPlayingMediaPeriod;
     }
     }
 
 
     /** Updates the queue with a reported timeline change. */
     /** Updates the queue with a reported timeline change. */
@@ -795,7 +796,7 @@ public class AnalyticsCollector
         readingMediaPeriod = updateMediaPeriodInfoToNewTimeline(readingMediaPeriod, timeline);
         readingMediaPeriod = updateMediaPeriodInfoToNewTimeline(readingMediaPeriod, timeline);
       }
       }
       this.timeline = timeline;
       this.timeline = timeline;
-      updateLastReportedPlayingMediaPeriod();
+      lastReportedPlayingMediaPeriod = lastPlayingMediaPeriod;
     }
     }
 
 
     /** Updates the queue with a reported start of seek. */
     /** Updates the queue with a reported start of seek. */
@@ -806,7 +807,7 @@ public class AnalyticsCollector
     /** Updates the queue with a reported processed seek. */
     /** Updates the queue with a reported processed seek. */
     public void onSeekProcessed() {
     public void onSeekProcessed() {
       isSeeking = false;
       isSeeking = false;
-      updateLastReportedPlayingMediaPeriod();
+      lastReportedPlayingMediaPeriod = lastPlayingMediaPeriod;
     }
     }
 
 
     /** Updates the queue with a newly created media period. */
     /** Updates the queue with a newly created media period. */
@@ -816,8 +817,9 @@ public class AnalyticsCollector
           new MediaPeriodInfo(mediaPeriodId, isInTimeline ? timeline : Timeline.EMPTY, windowIndex);
           new MediaPeriodInfo(mediaPeriodId, isInTimeline ? timeline : Timeline.EMPTY, windowIndex);
       mediaPeriodInfoQueue.add(mediaPeriodInfo);
       mediaPeriodInfoQueue.add(mediaPeriodInfo);
       mediaPeriodIdToInfo.put(mediaPeriodId, mediaPeriodInfo);
       mediaPeriodIdToInfo.put(mediaPeriodId, mediaPeriodInfo);
+      lastPlayingMediaPeriod = mediaPeriodInfoQueue.get(0);
       if (mediaPeriodInfoQueue.size() == 1 && !timeline.isEmpty()) {
       if (mediaPeriodInfoQueue.size() == 1 && !timeline.isEmpty()) {
-        updateLastReportedPlayingMediaPeriod();
+        lastReportedPlayingMediaPeriod = lastPlayingMediaPeriod;
       }
       }
     }
     }
 
 
@@ -835,6 +837,9 @@ public class AnalyticsCollector
       if (readingMediaPeriod != null && mediaPeriodId.equals(readingMediaPeriod.mediaPeriodId)) {
       if (readingMediaPeriod != null && mediaPeriodId.equals(readingMediaPeriod.mediaPeriodId)) {
         readingMediaPeriod = mediaPeriodInfoQueue.isEmpty() ? null : mediaPeriodInfoQueue.get(0);
         readingMediaPeriod = mediaPeriodInfoQueue.isEmpty() ? null : mediaPeriodInfoQueue.get(0);
       }
       }
+      if (!mediaPeriodInfoQueue.isEmpty()) {
+        lastPlayingMediaPeriod = mediaPeriodInfoQueue.get(0);
+      }
       return true;
       return true;
     }
     }
 
 
@@ -843,12 +848,6 @@ public class AnalyticsCollector
       readingMediaPeriod = mediaPeriodIdToInfo.get(mediaPeriodId);
       readingMediaPeriod = mediaPeriodIdToInfo.get(mediaPeriodId);
     }
     }
 
 
-    private void updateLastReportedPlayingMediaPeriod() {
-      if (!mediaPeriodInfoQueue.isEmpty()) {
-        lastReportedPlayingMediaPeriod = mediaPeriodInfoQueue.get(0);
-      }
-    }
-
     private MediaPeriodInfo updateMediaPeriodInfoToNewTimeline(
     private MediaPeriodInfo updateMediaPeriodInfoToNewTimeline(
         MediaPeriodInfo info, Timeline newTimeline) {
         MediaPeriodInfo info, Timeline newTimeline) {
       int newPeriodIndex = newTimeline.getIndexOfPeriod(info.mediaPeriodId.periodUid);
       int newPeriodIndex = newTimeline.getIndexOfPeriod(info.mediaPeriodId.periodUid);