SvxZoomItem includes text zoom level Ids unlike SfxUInt16Iem which only
includes zoom percent id.SfxUInt16Item is the base class for SvxZoomItem.

Change-Id: I8ad2a8cf48632853538aa2d99993f8dfccf49f4c
Reviewed-on: https://gerrit.libreoffice.org/14488Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>