Switch to night style when Smart Invert Colors is enabled

[1ec5]

NavigationMapView should automatically switch to the night style when the Smart Invert Colors option is enabled in iOS 11, based on UIAccessibilityIsInvertColorsEnabled() or the UIAccessibilityInvertColorsStatusDidChange notification. It’s possible that UIKit will take care of inverting the UI correctly when Smart Invert Colors is enabled, but we’d still need to choose the opposite style.

/ref https://github.com/mapbox/mapbox-navigation-ios/issues/423#issuecomment-324851696 /cc @ericrwolfe @frederoni @bsudekum

[1ec5]

mapbox/mapbox-gl-native#9859 tracks opting MGLMapView out of Smart Invert Colors, but it would still be up to this library to switch to the appropriate style.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

Stale.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.