Error when using custom styles and removeControl method

I'm getting the error: `Uncaught TypeError: Cannot read property 'recalculate' of undefined` after I use the map.removeControl method on the directions control. Also, it's only happening when using custom styles.

Here's a JSFiddle showing the issue: https://jsfiddle.net/bryantaxs/uomq0zvz/

Any thoughts on this one?

Start by running the linked JSFiddle and reproducing the error after calling map.removeControl on the directions control with custom styles. Trace the resulting `recalculate` access and verify that removing the control no longer throws the reported TypeError in that configuration.

Written by the indexing model from the issue text.