/usr/share/glib-2.0/schemas/ is in gnome-applets-data 3.18.2-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.battstat.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.charpick.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.cpufreq.enums.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.cpufreq.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.geyes.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.gweather.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.multiload.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.netspeed.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.stickynotes.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-applets.window-picker-applet.gschema.xml