src/vs/workbench/contrib/debug/browser/rawDebugSession.ts/RawDebugSession/stepBack
class RawDebugSession:	async stepBack(args: DebugProtocol.StepBackArguments): Promise<DebugProtocol.StepBackResponse | undefined> {
		if (this.capabilities.supportsStepBack) {
			const response = await this.send('stepBack', args);
			this.fireSimulatedContinuedEvent(args.threadId);
			return response;
		}
		return Promise.reject(new Error('stepBack not supported'));
	}