private boolean removeIf(Predicate<Tombstone> predicate) {
      boolean isTombstoneRemoved = removeUnexpiredIf(predicate);
      if (removeExpiredIf(predicate)) {
        isTombstoneRemoved = true;
      }
      return isTombstoneRemoved;
    }
For all tombstone this sweeper knows about call the predicate. If the predicate returns true
then remove the tombstone from any storage and update the memory estimate.

@return true if predicate ever returned true
geode-core/src/main/java/org/apache/geode/internal/cache/TombstoneService.java