Separate handling of oldTimeline == null case

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=164254522

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

@@ -986,18 +986,18 @@ import java.io.IOException;
           // The seek position was valid for the timeline that it was performed into, but the
           // timeline has changed and a suitable seek position could not be resolved in the new one.
           handleSourceInfoRefreshEndedPlayback(manifest, processedInitialSeekCount);
-          return;
-        }
+        } else {
           int periodIndex = periodPosition.first;
           long positionUs = periodPosition.second;
           MediaPeriodId periodId =
               mediaPeriodInfoSequence.resolvePeriodPositionForAds(periodIndex, positionUs);
           playbackInfo = new PlaybackInfo(periodId, periodId.isAd() ? 0 : positionUs, positionUs);
+          notifySourceInfoRefresh(manifest, processedInitialSeekCount);
+        }
       } else if (playbackInfo.startPositionUs == C.TIME_UNSET) {
         if (timeline.isEmpty()) {
           handleSourceInfoRefreshEndedPlayback(manifest, processedInitialSeekCount);
-          return;
-        }
+        } else {
           Pair<Integer, Long> defaultPosition = getPeriodPosition(0, C.TIME_UNSET);
           int periodIndex = defaultPosition.first;
           long startPositionUs = defaultPosition.second;
@@ -1005,8 +1005,11 @@ import java.io.IOException;
               startPositionUs);
           playbackInfo = new PlaybackInfo(periodId, periodId.isAd() ? 0 : startPositionUs,
               startPositionUs);
+          notifySourceInfoRefresh(manifest, processedInitialSeekCount);
         }
       }
+      return;
+    }
 
     MediaPeriodHolder periodHolder = playingPeriodHolder != null ? playingPeriodHolder
         : loadingPeriodHolder;