glocalfile: Fix access::can-trash if parent is symlink
glocalfile: Fix access::can-trash if parent is symlink

G_FILE_ATTRIBUTE_ACCESS_CAN_TRASH can be set to a wrong value if
its parent dir is a symlink. This is because the find_mountpoint_for()
function tries to find mountpoint for a filepath and expands symlinks
only in parent dirs. But in this case the path is already parent dir
and needs to be expanded first...

Closes: https://gitlab.gnome.org/GNOME/glib/issues/1522

endlessm/glib,endlessm/glib,endlessm/glib,endlessm/glib,endlessm/glib