Some Secret Service API backend implementations (like keepassxc) throws UnknownObject (instead of UnknownMethod as gnome-keyring do) after creating an item in the non-existent /org/freedesktop/secrets/aliases/default.
This patch add handling of UnknownObject to create default collection after failed creation of an item.
Example of DBus errors with SearchItems (in this case it throws the same errors as CreateItem):
gnome-keyring:
gdbus call --session --dest org.freedesktop.secrets --object-path /org/freedesktop/secrets/aliases/default --method org.freedesktop.Secret.Collection.SearchItems '{}'
Error: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface “org.freedesktop.Secret.Collection” on object at path /org/freedesktop/secrets/collection/keyringkeepassxc:
gdbus call --session --dest org.freedesktop.secrets --object-path /org/freedesktop/secrets/aliases/default --method org.freedesktop.Secret.Collection.SearchItems '{}'
Error: GDBus.Error:org.freedesktop.DBus.Error.UnknownObject: No such object path '/org/freedesktop/secrets/aliases/default'