also edited two examples in canvas comments

Change-Id: Iac82b462168f869f995c33bb2c639f3dbe09cbd5
Reviewed-on: https://gerrit.libreoffice.org/31715Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>