code: @Override
      public List<RevisionInternal> getRevisionHistory(RevisionInternal rev) {
          Document doc = getDocument(rev.getDocID());
          if (doc == null)
              return null;
          try {
              try {
                  if (!doc.selectRevID(rev.getRevID(), false))
                      return null;
              } catch (ForestException e) {
                  Log.e(TAG, "Error in getRevisionHistory() rev=" + rev, e);
                  return null;
              }
              List<RevisionInternal> history = new ArrayList<RevisionInternal>();
              do {
                  RevisionInternal ancestor = ForestBridge.revisionObject(
                          doc, rev.getDocID(), null, false);
                  if (ancestor == null)
                      break;
                  ancestor.setMissing(!doc.hasRevisionBody());
                  history.add(ancestor);
                  // TODO: implement once ancestorRevIDs param is given.
                  //if(ancestorRevIDs!=null&&ancestorRevIDs.contains(ancestor.getRevID()))
                  //    break;
              } while (doc.selectParentRev());
              return history;
          } finally {
              doc.free();
          }
      }
docs: TODO: Set<String> ancestorRevIDs as additional parameter