Make seekTo non-final so it can be overridden

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=135930574

library/src/main/java/com/google/android/exoplayer/SampleSourceTrackRenderer.java

@@ -113,7 +113,7 @@ protected void onEnabled(int track, long positionUs, boolean joining)
   }
 
   @Override
-  protected final void seekTo(long positionUs) throws ExoPlaybackException {
+  protected void seekTo(long positionUs) throws ExoPlaybackException {
     positionUs = shiftInputPosition(positionUs);
     enabledSource.seekToUs(positionUs);
     checkForDiscontinuity(positionUs);