extensions/typescript-language-features/src/experimentationService.ts/ExperimentationService/getTreatmentVariable
class ExperimentationService:	public async getTreatmentVariable<K extends keyof ExperimentTypes>(name: K, defaultValue: ExperimentTypes[K]): Promise<ExperimentTypes[K]> {
		const experimentationService = await this._experimentationServicePromise;
		try {
			const treatmentVariable = experimentationService.getTreatmentVariableAsync('vscode', name, /*checkCache*/ true) as Promise<ExperimentTypes[K]>;
			return treatmentVariable;
		} catch {
			return defaultValue;
		}
	}