anchor.diff:    /// Default is [DeviceCorporealType.slabHandheld].
     final DeviceCorporealType deviceCorporealType;
   
  +  /// If the phone is foldable, is it folded (true) or not (false).
  +  ///
  +  /// If the phone is not foldable, null.
  +  ///
  +  /// Default is null.
  +  final bool isFolded;
  +
     /// Number of users facing the screen.
     ///
     /// Null means 'unknown'.
  
positive.code:   /// Foldable phone.
    foldableHandheld,
  
    /// Slab-style phone.
    slabHandheld,
  
    /// Mobile tablet.
    tabletHandheld,
  
negative.code:   /// Creates additional data for a [MediaQuery] with explicit values.
    const ExperimentalMediaQueryData({
      this.deviceCorporealContext = DeviceCorporealContext.focused,
      this.deviceCorporealType = DeviceCorporealType.slateHandheld,
      this.isFolded,
      this.viewerCount = 1,
      this.viewingAngle = 0,
  