Enforce/honor per-vhost queue limit for all protocols

[SimonUnge]

Proposed Changes

The current vhost queue limit it's only applicable to AMQP 0.9.1 and "non-native" protocols.

This PR moves the check to rabbit_queue_type:declare

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[ansd]

This PR adds a regression: rabbit_vhost_limit:is_over_queue_limit/1 is now called twice for MQTT connections:

rabbitmq-server/deps/rabbitmq_mqtt/src/rabbit_mqtt_processor.erl

Lines 1357 to 1383 in ad6c173

	case rabbit_vhost_limit:is_over_queue_limit(VHost) of
	false ->
	rabbit_core_metrics:queue_declared(QName),
	Q0 = amqqueue:new(QName,
	none,
	_Durable = true,
	_AutoDelete = false,
	QOwner,
	QArgs,
	VHost,
	#{user => Username},
	QType),
	case rabbit_queue_type:declare(Q0, node()) of
	{new, Q} when ?is_amqqueue(Q) ->
	rabbit_core_metrics:queue_created(QName),
	{ok, Q};
	Other ->
	?LOG_ERROR("Failed to declare ~s: ~p",
	[rabbit_misc:rs(QName), Other]),
	{error, queue_declare}
	end;
	{true, Limit} ->
	?LOG_ERROR("cannot declare ~s because "
	"queue limit ~p in vhost '~s' is reached",
	[rabbit_misc:rs(QName), Limit, VHost]),
	{error, queue_limit_exceeded}
	end

[SimonUnge]

@ansd Hmmm, totally missed that check. It would only check if twice with a 'false' result I guess... Although something could slip in-between perhaps. I can update the mqtt_processor code to just handle the protocol error return value of rabbit_queue_type:declare?

[ansd]

I can update the mqtt_processor code to just handle the protocol error return value of rabbit_queue_type:declare?

That would be great, thank you!