boxZoomBounds no longer available in boxzoomend event

[itsmequinn]

Release v0.49.0 removed the boxZoomBounds from booxzoomend events but the documentation for boxzoomend still says that a boxZoomBounds should be available as part of that event's data.

mapbox-gl-js version: v0.49.0 and later

browser: Chrome Version 71.0.3578.98 (Official Build) (64-bit)

Steps to Trigger Behavior

1. Load a mapbox gl js map
2. Shift and click+drag to trigger a boxzoomend event
3. Observe the event's data and see that it only contains originalEvent, target and type properties

Expected Behavior

bozZoomBounds should contain the bounds of the map after zooming

Actual Behavior

boxZoomBounds does not exist

[ryanhamley]

Closed by #7741