accountmodel: Make the alias anti-duplication function invokable
accountmodel: Make the alias anti-duplication function invokable

For QML and tests

Change-Id: I5957cc0e96a8476e60b1d325f00c49d425270bf0
Reviewed-by: Stepan Salenikovich <bebb1f1b8bb7363930c4153df8cb235b803d485d@savoirfairelinux.com>

savoirfairelinux/ring-lrc,savoirfairelinux/ring-lrc,savoirfairelinux/ring-lrc,savoirfairelinux/ring-lrc,savoirfairelinux/ring-lrc