Remove unnecessary null check.

Issue #2462

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147731351

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

@@ -101,9 +101,6 @@ import java.util.Locale;
 
   @Override
   public void onTimelineChanged(Timeline timeline, Object manifest) {
-    if (timeline == null) {
-      return;
-    }
     int periodCount = timeline.getPeriodCount();
     int windowCount = timeline.getWindowCount();
     Log.d(TAG, "sourceInfo [periodCount=" + periodCount + ", windowCount=" + windowCount);