src/vs/workbench/services/extensions/common/rpcProtocol.ts/MessageIO/_requestMixedArgs
class MessageIO:	private static _requestMixedArgs(req: number, rpcId: number, method: string, args: VSBuffer[], argsType: ArgType[], usesCancellationToken: boolean): VSBuffer {
		const methodBuff = VSBuffer.fromString(method);

		let len = 0;
		len += MessageBuffer.sizeUInt8();
		len += MessageBuffer.sizeShortString(methodBuff);
		len += MessageBuffer.sizeMixedArray(args, argsType);

		let result = MessageBuffer.alloc(usesCancellationToken ? MessageType.RequestMixedArgsWithCancellation : MessageType.RequestMixedArgs, req, len);
		result.writeUInt8(rpcId);
		result.writeShortString(methodBuff);
		result.writeMixedArray(args, argsType);
		return result.buffer;
	}