src/vs/platform/configuration/common/configuration.ts/isConfigurationUpdateOverrides
export function isConfigurationUpdateOverrides(thing: any): thing is IConfigurationUpdateOverrides {
	return thing
		&& typeof thing === 'object'
		&& (!thing.overrideIdentifiers || types.isArray(thing.overrideIdentifiers))
		&& !thing.overrideIdentifier
		&& (!thing.resource || thing.resource instanceof URI);
}