extensions/references-view/src/calls/model.ts/CallsTreeInput/constructor
class CallsTreeInput:	constructor(
		readonly location: vscode.Location,
		readonly direction: CallsDirection,
	) {
		this.title = direction === CallsDirection.Incoming
			? localize('title.callers', 'Callers Of')
			: localize('title.calls', 'Calls From');
	}