anchor.diff:  ///    [Locale].
   class Locale {
     /// Creates a new Locale object. The first argument is the
  -  /// primary language subtag, the second is the region subtag.
  +  /// primary language subtag, the second is the region (also
  +  /// referred to as 'country') subtag.
     ///
     /// For example:
     ///
  
positive.code:   /// [script](http://unicode.org/cldr/latest/common/validity/script.xml) and
    /// [region](http://unicode.org/cldr/latest/common/validity/region.xml) for
    /// each of languageCode, scriptCode and countryCode respectively.
    ///
    /// Validity is not checked by default, but some methods may throw away
    /// invalid data.
  
negative.code:   /// ```
    ///
    /// The primary language subtag must not be null. The region subtag is
    /// optional. When there is no region/country subtag, the parameter should
    /// be omitted or passed `null` instead of an empty-string.
    ///
    /// The subtag values are _case sensitive_ and must be one of the valid
    /// subtags according to CLDR supplemental data:
  