/usr/share/glib-2.0/ is in gnome-panel-data 1:3.18.2-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/glib-2.0/schemas/
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.applet.clock.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.applet.fish.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.applet.window-list.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.applet.workspace-switcher.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.enums.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.launcher.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.menu-button.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.object.gschema.xml
/usr/share/glib-2.0/schemas/org.gnome.gnome-panel.toplevel.gschema.xml