function markDefaultPropsAsUnresolved(component) {
    components.set(component.node, {
      defaultProps: 'unresolved',
    });
  }
Marks a component's DefaultProps declaration as "unresolved". A component's DefaultProps is
marked as "unresolved" if we cannot safely infer the values of its defaultProps declarations
without risking false negatives.
@param   {Object} component The component to mark.
@returns {void}