docs: public static int getStickyFooterPositionByIdentifier(DrawerBuilder drawer, long identifier) {
          if (identifier != -1) {
              if (drawer.mStickyFooterView != null && drawer.mStickyFooterView instanceof LinearLayout) {
                  LinearLayout footer = (LinearLayout) drawer.mStickyFooterView;
  
                  int shadowOffset = 0;
                  for (int i = 0; i < footer.getChildCount(); i++) {
                      Object o = footer.getChildAt(i).getTag(R.id.material_drawer_item);
  
                      //count up the shadowOffset to return the correct position of the given item
                      if (o == null && drawer.mStickyFooterDivider) {
                          shadowOffset = shadowOffset + 1;
                      }
  
                      if (o != null && o instanceof IDrawerItem && ((IDrawerItem) o).getIdentifier() == identifier) {
                          return i - shadowOffset;
                      }
                  }
              }
          }
  
          return -1;
      }