Fully document MappingTrackSelector

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162721489

library/core/src/main/java/com/google/android/exoplayer2/trackselection/DefaultTrackSelector.java

@@ -33,9 +33,7 @@ import java.util.List;
 import java.util.concurrent.atomic.AtomicReference;
 
 /**
- * A {@link MappingTrackSelector} that allows configuration of common parameters. It is safe to call
- * the methods of this class from the application thread. See {@link Parameters#Parameters()} for
- * default selection parameters.
+ * A {@link MappingTrackSelector} suitable for most use cases.
  */
 public class DefaultTrackSelector extends MappingTrackSelector {