src/vs/workbench/services/update/browser/updateService.ts/BrowserUpdateService/doCheckForUpdates
class BrowserUpdateService:	private async doCheckForUpdates(explicit: boolean): Promise<IUpdate | null> {
		if (this.environmentService.options && this.environmentService.options.updateProvider) {
			const updateProvider = this.environmentService.options.updateProvider;

			// State -> Checking for Updates
			this.state = State.CheckingForUpdates(explicit);

			const update = await updateProvider.checkForUpdate();
			if (update) {
				// State -> Downloaded
				this.state = State.Ready({ version: update.version, productVersion: update.version });
			} else {
				// State -> Idle
				this.state = State.Idle(UpdateType.Archive);
			}

			return update;
		}

		return null; // no update provider to ask
	}