docs: @UiThread
      public void notifyChildRangeChanged(int parentPosition, int childPositionStart, int itemCount) {
          P parent = mParentList.get(parentPosition);
          int flatParentPosition = getFlatParentPosition(parentPosition);
          ExpandableWrapper<P, C> parentWrapper = mFlatItemList.get(flatParentPosition);
          parentWrapper.setParent(parent);
          if (parentWrapper.isExpanded()) {
              int flatChildPosition = flatParentPosition + childPositionStart + 1;
              for (int i = 0; i < itemCount; i++) {
                  ExpandableWrapper<P, C> child
                          = parentWrapper.getWrappedChildList().get(childPositionStart + i);
                  mFlatItemList.set(flatChildPosition + i, child);
              }
              notifyItemRangeChanged(flatChildPosition, itemCount);
          }
      }