@Override
  boolean areSerializedFieldsEqual(Filter other) {
    return true;
  }
Default implementation so that writers of custom filters aren't forced to implement.
@return true if and only if the fields of the filter that are serialized are equal to the
        corresponding fields in other. Used for testing.
hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FilterBase.java