uniformMargin function
The part of a host's padding that is the same on every side.
It is a margin around what fitBounds frames rather than room kept clear
of an overlay, so on Google Maps it is applied by the fit, not by the map
view. See googleViewPadding.
Implementation
double uniformMargin(EdgeInsets padding) => max(
0,
[padding.left, padding.top, padding.right, padding.bottom].reduce(min),
);