This way the example buttons will have a name for better
accessibility, instead of being blank.

Change-Id: Ib8a509bc7a9895297eecd8a0db9455f367d93159
Reviewed-on: https://gerrit.libreoffice.org/73171
Tested-by: Jenkins
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>