public void includeTimestamp(final ExtendedCell cell) {
    includeTimestamp(cell.getTimestamp());
    if (PrivateCellUtil.isDeleteColumnOrFamily(cell)) {
      includeTimestamp(0);
    }
  }
Update the current TimestampRange to include the timestamp from <code>cell</code>. If the Key
is of type DeleteColumn or DeleteFamily, it includes the entire time range from 0 to timestamp
of the key.
@param cell the Cell to include
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/TimeRangeTracker.java