/usr/share/glib-2.0/schemas/ is in mate-applets-common 1.20.1-3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/glib-2.0/schemas/org.mate.drivemount.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.battstat.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.charpick.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.command.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.cpufreq.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.geyes.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.multiload.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.netspeed.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.panel.applet.timer.gschema.xml
/usr/share/glib-2.0/schemas/org.mate.stickynotes.gschema.xml