LatLngBounds: Fix constrain when crossing antimeridian

[brunoabinader]

This PR fixes the constraint behavior when crossing the antimeridian, but also:

• Fixes an issue that caused panning to be set to false when the longitude value that was equal to its wrapped one e.g. when doing a full round over the globe;
• Constrain axes separately in LatLngBounds: this fixes an issue when the bounds crosses the antimeridian and only latitude needed to be constrained;

This PR is an alternative to #13906.

Closes #13672, follow up from #13871

/cc @tobrun

[LukasPaczos]

I've quickly tested this one and it works well for #13672, however, in contrast to #13906 it doesn't fix #13770 anymore. This is because when the gesture is in progress we are allowing to wrap around the world if the offset exceeds the antimeridian in here.

I think the possible solution can be ignoring, or changing the behavior of the isGestureInProgess flag if the camera constraint is set? Do you think this could be a part of this PR as well @brunoabinader?

[brunoabinader]

I think the possible solution can be ignoring, or changing the behavior of the isGestureInProgess flag if the camera constraint is set? Do you think this could be a part of this PR as well @brunoabinader?

Good point @LukasPaczos - I think we can special case for whether camera bounds is present or not in that line 👍

[brunoabinader]

This PR also changes the behavior of the internal coordinates stored in Transform. When a camera bound is set, we store unwrapped longitudes and use them to properly calculate bounds check in edge cases such as e.g. when the world horizontal span is visually repeated on the map view. Unwrapped values are also used when transforming screen coordinates into geographical ones (i.e. moveBy uses it).

Important to notice the unwrapped longitude value does not leak outside Transform, unless explicitedly requested when passing LatLng::Unwrapped to Transform.getLatLng(). Realizing this actually helped finding out a "bug" in flyTo behavior, which was throwing unwrapped values when the fly camera movement crosses the antimeridian.

[LukasPaczos]

I can confirm that this resolves both #13672 and #13770 🎉

[alexshalamov]

👍 and thanks for for the explanation.

[pozdnyakov]

LGTM with minor nits

[tmpsantos]

Great stuff! kudos