prefs: Remove dark theme pref
It's more trouble than it's worth. https://bugzilla.gnome.org/show_bug.cgi?id=707206 https://bugzilla.gnome.org/show_bug.cgi?id=742040 https://bugzilla.gnome.org/show_bug.cgi?id=742333 https://bugzilla.gnome.org/show_bug.cgi?id=649358
parent
a59e2cfa