This DEV-only field was added in 836331ba5f69f2cc53b273ec073fae116db14302 by @sebmarkbage but it's not being used anymore to my knowledge.
current,
  workInProgress,
  Component,
  nextProps: any,
  renderLanes,
) {
  if (__DEV__) {
    if (workInProgress.type !== workInProgress.elementType) {
      
      
      const innerPropTypes = Component.propTypes;
      if (innerPropTypes) {
        checkPropTypes(
          innerPropTypes,
          nextProps, 
          'prop',
          getComponentNameFromType(Component),
        );