src/vs/workbench/contrib/tasks/browser/abstractTaskService.ts/AbstractTaskService/_handleError
class AbstractTaskService:	private _handleError(err: any): void {
		let showOutput = true;
		if (err instanceof TaskError) {
			const buildError = <TaskError>err;
			const needsConfig = buildError.code === TaskErrors.NotConfigured || buildError.code === TaskErrors.NoBuildTask || buildError.code === TaskErrors.NoTestTask;
			const needsTerminate = buildError.code === TaskErrors.RunningTask;
			if (needsConfig || needsTerminate) {
				this._notificationService.prompt(buildError.severity, buildError.message, [{
					label: needsConfig ? ConfigureTaskAction.TEXT : nls.localize('TerminateAction.label', "Terminate Task"),
					run: () => {
						if (needsConfig) {
							this._runConfigureTasks();
						} else {
							this._runTerminateCommand();
						}
					}
				}]);
			} else {
				this._notificationService.notify({ severity: buildError.severity, message: buildError.message });
			}
		} else if (err instanceof Error) {
			const error = <Error>err;
			this._notificationService.error(error.message);
			showOutput = false;
		} else if (Types.isString(err)) {
			this._notificationService.error(<string>err);
		} else {
			this._notificationService.error(nls.localize('TaskSystem.unknownError', 'An error has occurred while running a task. See task log for details.'));
		}
		if (showOutput) {
			this._showOutput();
		}
	}