Any symbols (including class properties) that should be visible
outside the module it's defined in need to be defined as global.
For now gjs still allows the access for 'const', but get rid of
the warnings spill now by changing it.
https://bugzilla.gnome.org/show_bug.cgi?id=785084
If a sandboxed app requests access to some system resource (camera,
microphone, location), the portal frontend needs to ask the user
for permission. In GNOME, we want this to be a system modal dialog,
so provide an org.freedesktop.impl.portal.access implementation
that exposes a generic system modal permission dialog on the bus.
https://bugzilla.gnome.org/show_bug.cgi?id=768669
