src/vs/platform/userDataSync/common/userDataSync.ts/getLastSyncResourceUri
export function getLastSyncResourceUri(collection: string | undefined, syncResource: SyncResource, environmentService: IEnvironmentService, extUri: IExtUri): URI {
	return extUri.joinPath(environmentService.userDataSyncHome, ...getPathSegments(collection, syncResource, `lastSync${syncResource}.json`));
}