TrackSize.minmax constructor
Creates a track size that defines a size range greater than or equal to min and less than or equal to max.
If max is smaller than min, then max is ignored and the function is treated as min. As a maximum, a flex value
sets the track's flex factor. It is invalid as a minimum.
Implementation
const factory TrackSize.minmax(TrackSize min, TrackSize max) = _MinMaxTrackSize;