src/vs/workbench/api/common/extHostLabelService.ts/ExtHostLabelService/$registerResourceLabelFormatter
class ExtHostLabelService:	$registerResourceLabelFormatter(formatter: ResourceLabelFormatter): IDisposable {
		const handle = this._handlePool++;
		this._proxy.$registerResourceLabelFormatter(handle, formatter);

		return toDisposable(() => {
			this._proxy.$unregisterResourceLabelFormatter(handle);
		});
	}