Add LatLngBounds.contains() method

[ryanhamley]

Motivation

I'm splitting this request out from #7090 in which several different LatLng and LatLngBounds methods were brought up. GL Native has a LatLngBounds.contains utility method which is missing in JS. Adding this method to JS would increase parity between GL implementations and provide a useful method to users.

Design

I can see two possibilities.

1. A static method on LatLngBounds

LatLngBounds.contains(bounds, point)

2. An instance method

const bounds = new LatLngBounds([sw, ne]);
bounds.contains(point);

I'd say the instance method is preferable since all other methods on LatLngBounds are also instance methods. The static method would mostly be useful as a pure utility method in which you may want to check arbitrary bounds for a point, but does that have many use cases? I'm unsure.

contains should be able to check that a bounding box contains a point or a CanonicalTileID, as the Native implementation does. Native also checks unwrapped bounds, but that concept isn't well defined in JS and I think we can side step that implementation for now.

Implementation

We should be able to just port the C++ implementation
https://github.com/mapbox/mapbox-gl-native/blob/master/src/mbgl/util/tile_range.hpp#L40

[FernandoKGA]

This topic has already been opened as an issue here: #4278, but I don't think they got it correctly or it isn't really doable. I had came across the same issue, probably you want check if it contains the point, one of the members, @mollymerp suggested using Turf.js, #4278 (comment).

But in my case, I want to check if the bounds contain a marker with a popup in the same position given it's coordinates, in order to block an insertion, and this should be done with an layer I do think, however, I don't know how to do it yet.

[ryanhamley]

Thanks for pointing that ticket out. The lack of methods like this was mostly due to a conceptual way of thinking about Mapbox GL JS as a rendering library, not a geospatial query library. But given that there's user demand, it's straightforward to implement and it brings JS into parity with Native, I think it's ok to move forward with this. We'd welcome a PR if you're interested in adding this @FernandoKGA

[FernandoKGA]

I would love to @ryanhamley , however, I don't have so much time to develop a topic like this now as I'm studying, in addition, I do not have enough experience or practice with JS, yet. I'm using the API to develop a web project as a final test on one of my subjects at university. Probably by the time I will have finished the project, someone would already done it. (I think...)

[ryanhamley]

The GL JS implementation of this will need to implement all 3 definitions of contains in the GL Native repo as seen in https://github.com/mapbox/mapbox-gl-native/blob/master/src/mbgl/util/geo.cpp#L37-L65