ef807619e9
Plain classes are private to their file, so accessing them from
another module results in the following warning:
That property was defined with 'let' or 'const' inside the module.
This was previously supported, but is not correct according to the
ES6 standard.
Fix by assigning the class to a public variable instead.
(Eventually switching to ES6 modules with proper imports/exports will
fix this as well)
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1512>