Is there a reason the parameter name for ForwardingMap.remove(Object object) does not match the interface: Map.remove(Object key)?  In short: 'object' != 'key'
If yes, please kindly explain the history.
Else, can we rename to 'key' to match the interface?
public void testComplementOfSubRangeSet() {
    for (Range<Integer> range1 : QUERY_RANGES) {
      for (Range<Integer> range2 : QUERY_RANGES) {
        TreeRangeSet<Integer> rangeSet = TreeRangeSet.create();
        rangeSet.add(range1);
        rangeSet.add(range2);
        for (Range<Integer> subRange : QUERY_RANGES) {
          testViewAgainstExpected(
              expectedComplement(expectedSubRangeSet(rangeSet, subRange)),
              rangeSet.subRangeSet(subRange).complement());
        }
      }
    }
  }
  public void testRangesByUpperBound() {
    for (Range<Integer> range1 : QUERY_RANGES) {
      for (Range<Integer> range2 : QUERY_RANGES) {
        TreeRangeSet<Integer> rangeSet = TreeRangeSet.create();
        rangeSet.add(range1);
        rangeSet.add(range2);
        NavigableMap<Cut<Integer>, Range<Integer>> expectedRangesByUpperBound = Maps.newTreeMap();
        for (Range<Integer> range : rangeSet.asRanges()) {
          expectedRangesByUpperBound.put(range.upperBound, range);
        }
        testNavigationAgainstExpected(
            expectedRangesByUpperBound,
            new TreeRangeSet.RangesByUpperBound<Integer>(rangeSet.rangesByLowerBound),
            CUTS_TO_TEST);
      }
    }