default is 12

(cherry picked from commit dc9abefa)

Conflicts:
	officecfg/registry/schema/org/openoffice/Office/Common.xcs
	svtools/inc/svtools/accessibilityoptions.hxx
	svtools/source/inc/configitems/accessibilityoptions_const.hxx

Change-Id: Ic035b34bbcde426fa8fb76df16f84786908e18fa