function getDefault(classDefinition, propertyId) {
  const classProperties = classDefinition.properties;
  if (!defined(classProperties)) {
    return undefined;
  }

  const classProperty = classProperties[propertyId];
  if (defined(classProperty) && defined(classProperty.default)) {
    let value = classProperty.default;
    if (classProperty.isArray) {
      value = clone(value, true);
    }
    value = classProperty.normalize(value);
    return classProperty.unpackVectorAndMatrixTypes(value);
  }
}
Returns a typed array containing the property values for the property with the given semantic.

@param {string} semantic The case-sensitive semantic of the property.
@returns {*} The typed array containing the property values or <code>undefined</code> if the property values are not stored in a typed array.

@private