* AptUrl/gtk/backend/__init__.py: Drop "action-done" signal definition; update-manager's GTK backend already defines it with different arguments, so this is ineffective and confusing. * AptUrl/gtk/GtkUI.py, _on_backend_done(): Add additional error signal arguments, as defined by update-manager's backend. * AptUrl/gtk/backend/InstallBackend{Aptdaemon,Synaptic}.py: Call action-done signal with error arguments. (LP: #1103024)