docs: public boolean bind(@NonNull ViewDataBinding binding, T item) {
          if (variableId == VAR_NONE) {
              return false;
          }
          boolean result = binding.setVariable(variableId, item);
          if (!result) {
              Utils.throwMissingVariable(binding, variableId, layoutRes);
          }
          if (extraBindings != null) {
              for (int i = 0, size = extraBindings.size(); i < size; i++) {
                  int variableId = extraBindings.keyAt(i);
                  Object value = extraBindings.valueAt(i);
                  if (variableId != VAR_NONE) {
                      binding.setVariable(variableId, value);
                  }
              }
          }
          return true;
      }