INT-3433 commit

INT-3433: Fixed NIO deadlock (or timout if the CallerBlocksPolicy is used) with Bounded ThreadPoolTaskExecutor.

JIRA: https://jira.spring.io/browse/INT-3433

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You mean the whole try block? But it sets the `moreDataAvailable` flag and without it assembler might not read all the data available. I run a test and it confirmed it - not all messages were delivered.