online-accounts: handle unbranded chat providers

https://bugzilla.gnome.org/show_bug.cgi?id=706148
online-accounts: make the list boxes in "Other" expand vertically

https://bugzilla.gnome.org/show_bug.cgi?id=706148
online-accounts: use the async function to get all the providers

https://bugzilla.gnome.org/show_bug.cgi?id=706148
configure.ac: bump GOA dependency to 3.9.90

https://bugzilla.gnome.org/show_bug.cgi?id=706148