[FEATURE] Simplify background colouring when specifying multiple TileLayers

[JaffaKetchup]

What do you want implemented?

At the moment, every TileLayer has a backgroundColor property that defaults to a grey color. This means that, to layer multiple TileLayers on top of each other (for example, one with a base map, and one with some hiking trails), the user must manually set the backgroundColor property on the top layer to Colors.transparent.

Instead, a simpler interaction might be to remove the backgroundColor property from the TileLayer (replacing it's internal usage with Colors.transparent), and add it to MapOptions. A standard ColoredBox can then be inserted internally as the lowest layer, with its color as backgroundColor.

What other alternatives are available?

No response

Can you provide any other information?

No response

Severity

Annoying: Currently have to use workarounds