function getPropertyNameNode(node) {
  if (
    node.key
    || node.type === 'MethodDefinition'
    || node.type === 'Property'
  ) {
    return node.key;
  }
  if (node.type === 'MemberExpression') {
    return node.property;
  }
  return null;
}
Get node with property's name
@param {Object} node - Property.
@returns {Object} Property name node.