code: @InterfaceAudience.Private
      protected void revisionAdded(DocumentChange change, boolean notify) {
          if (change.getRevisionId() != null) {
              String revID = change.getWinningRevisionID();
              if (revID == null)
                  return;  // current revision didn't change
  
              if (currentRevision != null && !revID.equals(currentRevision.getId())) {
                  RevisionInternal rev = change.getWinningRevisionIfKnown();
                  if (rev == null)
                      forgetCurrentRevision();
                  else if (rev.isDeleted())
                      currentRevision = null;
                  else
                      currentRevision = new SavedRevision(this, rev);
              }
          } else {
              // Document was purged!
              currentRevision = null;
          }
  
          if (notify) {
              for (ChangeListener listener : changeListeners)
                  listener.changed(new ChangeEvent(this, change));
          }
      }
  
      @InterfaceAudience.Private
      protected void forgetCurrentRevision() {
          currentRevision = null;
      }
  }
docs: Notification from the CBLDatabase that a (current, winning) revision has been added
  
  @exclude