src/vs/workbench/services/integrity/electron-sandbox/integrityService.ts/IntegrityService/_isPure
class IntegrityService:	private async _isPure(): Promise<IntegrityTestResult> {
		const expectedChecksums = this.productService.checksums || {};

		await this.lifecycleService.when(LifecyclePhase.Eventually);

		const allResults = await Promise.all(Object.keys(expectedChecksums).map(filename => this._resolve(<AppResourcePath>filename, expectedChecksums[filename])));

		let isPure = true;
		for (let i = 0, len = allResults.length; i < len; i++) {
			if (!allResults[i].isPure) {
				isPure = false;
				break;
			}
		}

		return {
			isPure: isPure,
			proof: allResults
		};
	}