src/vs/platform/extensionManagement/node/extensionManagementService.ts/ExtensionManagementService/preUninstallExtension
class ExtensionManagementService:	private async preUninstallExtension(extension: ILocalExtension): Promise<void> {
		const exists = await pfs.Promises.exists(extension.location.fsPath);
		if (!exists) {
			throw new Error(nls.localize('notExists', "Could not find extension"));
		}
		this.logService.info('Uninstalling extension:', extension.identifier.id);
		this._onUninstallExtension.fire(extension.identifier);
	}