Added KIM_DUPLICATE_UI_REQUEST_ERR error so UI can indicate it cancelled
its dialog due to getting multiple identical dialogs at the same time.

Commit By: lxs



Revision: 20942
Changed Files:
U   trunk/src/kim/lib/kim_credential.c
U   trunk/src/kim/lib/kim_errors.et
U   trunk/src/kim/lib/kim_identity.c
U   trunk/src/kim/lib/kim_selection_hints.c