anchor.diff:    ///
     /// Typically this is a list of [FlatButton] widgets.
     ///
  -  /// These widgets will be wrapped in a [ButtonBar].
  +  /// These widgets will be wrapped in a [ButtonBar], which introduces 8 pixels
  +  /// of padding on each side.
  +  ///
  +  /// If the [title] is not null but the [content] _is_ null, then an extra 20
  +  /// pixels of padding is added above the [ButtonBar] to separate the [title]
  +  /// from the [actions].
     final List<Widget> actions;
   
     @override
  
positive.code: 
      if (title != null) {
        children.add(new Padding(
          padding: titlePadding ?? new EdgeInsetsDirectional.fromSTEB(24.0, 24.0, 24.0, content == null ? 20.0 : 0.0),
          child: new DefaultTextStyle(
            style: Theme.of(context).textTheme.title,
            child: title,
  
negative.code:   /// Creates a simple dialog.
    ///
    /// Typically used in conjunction with [showDialog].
    ///
    /// The [titlePadding] and [contentPadding] arguments must not be null.
    const SimpleDialog({
      Key key,
      this.title,
      this.titlePadding: const EdgeInsets.fromLTRB(24.0, 24.0, 24.0, 0.0),
      this.children,
      this.contentPadding: const EdgeInsets.fromLTRB(0.0, 12.0, 0.0, 16.0),
    }) : assert(titlePadding != null),
         assert(contentPadding != null),
         super(key: key);
  
    /// The (optional) title of the dialog is displayed in a large font at the top
    /// of the dialog.
  