gentoo-overlay/gnome-base/gnome-control-center/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
	<herd>gnome</herd>
	<use>
		<flag name="colord">Support color management using
			<pkg>x11-misc/colord</pkg></flag>
		<flag name="cheese">Add support for taking pictures for the user
			accounts panel using <pkg>media-video/cheese</pkg></flag>
		<flag name="gnome-online-accounts">Enable configuration panel for
			<pkg>net-libs/gnome-online-accounts</pkg> accounts</flag>
		<flag name="socialweb">Add support for desktop background images from
			Flickr using <pkg>net-libs/libsocialweb</pkg></flag>
		<flag name="systemd">Use <pkg>sys-apps/systemd</pkg> instead of
			<pkg>sys-auth/consolekit</pkg> for session tracking</flag>
		<flag name="wacom">Enable support for Wacom tablets and drawing
			devices</flag>
	</use>
</pkgmetadata>