ArrangementMode.Resizable should honor Dim.Auto (min/maxContentSize)

[tig]

If a View is set like this:

var view = new Window () // movable & resizable
{
  Width = Dim.Auto (Content, minimumContentSize: 10, maximumContentSize: 20);
}

I should not be able to resize the View to be any smaller than 10 + adornments or larger than 20 + adornments.

The current code is blind to DimAuto and just overwrites:

                   case ViewArrangement.LeftResizable:
                       // Get how much the mouse has moved since the start of the drag
                       // and adjust the height of the parent by that amount
                       int deltaX = parentLoc.X - Parent.Frame.X;
                       int newWidth = Math.Max (minWidth, Parent.Frame.Width - deltaX);

                       if (newWidth != Parent.Frame.Width)
                       {
                           Parent.Width = newWidth;
                           Parent.X = parentLoc.X - _startGrabPoint.X;
                       }

                       break;

I think there's a way to do this...