YT-20068: In TRequestQueue, fix a couple of bugs (one theoretical, one probably practical).

Theoretical: a failure in a heavy handler would lead to leaking 1) concurrency
counter and 2) the need to initiate further processing
of requests in the queue. Unlikely in practice as the only reason a heavy
handler can fail is something going wrong when deserializing a request.

Practical: ScheduleRequestsFromQueue may be reentered (because of
a synchronous Subscribe call on a throttler future). There's a latch making
a reentrant call noop. However, that would, again, lead to leaking the
need to initiate further processing of requests in the queue.

0 files changed, 0 insertions, 0 deletions