Avoid resetting the tracks on BLWE media source reinitialization

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=145998158

demo/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -321,7 +321,7 @@ public class PlayerActivity extends Activity implements OnClickListener, ExoPlay
       if (haveResumePosition) {
         player.seekTo(resumeWindow, resumePosition);
       }
-      player.prepare(mediaSource, !haveResumePosition, !haveResumePosition);
+      player.prepare(mediaSource, !haveResumePosition, false);
       playerNeedsSource = false;
       updateButtonVisibilities();
     }