Fix condition for detecting that an ad has ended

onEnded was being called also for content finishing, as in this case the playing
ad index changed (from INDEX_UNSET to 0). Fix this test so we only detect ads
finishing.

Also add logging for onEnded callbacks.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179167737

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -703,6 +703,9 @@ public final class ImaAdsLoader extends Player.DefaultEventListener implements A
       for (int i = 0; i < adCallbacks.size(); i++) {
       for (int i = 0; i < adCallbacks.size(); i++) {
         adCallbacks.get(i).onEnded();
         adCallbacks.get(i).onEnded();
       }
       }
+      if (DEBUG) {
+        Log.d(TAG, "VideoAdPlayerCallback.onEnded in onPlayerStateChanged");
+      }
     }
     }
   }
   }
 
 
@@ -798,16 +801,20 @@ public final class ImaAdsLoader extends Player.DefaultEventListener implements A
 
 
   private void updateImaStateForPlayerState() {
   private void updateImaStateForPlayerState() {
     boolean wasPlayingAd = playingAd;
     boolean wasPlayingAd = playingAd;
+    int oldPlayingAdIndexInAdGroup = playingAdIndexInAdGroup;
     playingAd = player.isPlayingAd();
     playingAd = player.isPlayingAd();
+    playingAdIndexInAdGroup = playingAd ? player.getCurrentAdIndexInAdGroup() : C.INDEX_UNSET;
     if (!sentContentComplete) {
     if (!sentContentComplete) {
-      boolean adFinished = (wasPlayingAd && !playingAd)
-          || playingAdIndexInAdGroup != player.getCurrentAdIndexInAdGroup();
+      boolean adFinished = wasPlayingAd && playingAdIndexInAdGroup != oldPlayingAdIndexInAdGroup;
       if (adFinished) {
       if (adFinished) {
         // IMA is waiting for the ad playback to finish so invoke the callback now.
         // IMA is waiting for the ad playback to finish so invoke the callback now.
         // Either CONTENT_RESUME_REQUESTED will be passed next, or playAd will be called again.
         // Either CONTENT_RESUME_REQUESTED will be passed next, or playAd will be called again.
         for (int i = 0; i < adCallbacks.size(); i++) {
         for (int i = 0; i < adCallbacks.size(); i++) {
           adCallbacks.get(i).onEnded();
           adCallbacks.get(i).onEnded();
         }
         }
+        if (DEBUG) {
+          Log.d(TAG, "VideoAdPlayerCallback.onEnded in onTimelineChanged/onPositionDiscontinuity");
+        }
       }
       }
       if (!wasPlayingAd && playingAd) {
       if (!wasPlayingAd && playingAd) {
         int adGroupIndex = player.getCurrentAdGroupIndex();
         int adGroupIndex = player.getCurrentAdGroupIndex();
@@ -819,7 +826,6 @@ public final class ImaAdsLoader extends Player.DefaultEventListener implements A
         }
         }
       }
       }
     }
     }
-    playingAdIndexInAdGroup = playingAd ? player.getCurrentAdIndexInAdGroup() : C.INDEX_UNSET;
   }
   }
 
 
   private void resumeContentInternal() {
   private void resumeContentInternal() {