anchor.diff:    return result;
   }
   
  -/// Controls specific aspects of the embedder interface.
  +/// Controls specific aspects of the operating system's graphical interface and
  +/// how it interacts with the application.
   class SystemChrome {
     SystemChrome._();
   
     /// Specifies the set of orientations the application interface can
     /// be displayed in.
     ///
  -  /// Arguments:
  -  ///
  -  ///  * [orientation]: A list of [DeviceOrientation] enum values. The empty
  -  ///    list is synonymous with having all options enabled.
  +  /// The `orientation` argument is a list of [DeviceOrientation] enum values.
  +  /// The empty list is synonymous with having all options enabled.
     static Future<Null> setPreferredOrientations(List<DeviceOrientation> orientations) async {
       await PlatformMessages.invokeMethod(
         _kChannelName,
  
positive.code:     }
  
      if (style == _latestStyle) {
        // Trivial success; no need to queue a microtask.
        return;
      }
  
  
negative.code:   }
  
    /// Specifies the description of the current state of the application as it
    /// pertains to the application switcher (also known as "recent tasks").
    ///
    /// Any part of the description that is unsupported on the current platform
    /// will be ignored.
    static Future<Null> setApplicationSwitcherDescription(ApplicationSwitcherDescription description) async {
      await PlatformMessages.invokeMethod(
        _kChannelName,
  