Catch exception from shm connection start()

[jiayisuse]

Summary: util::ringbuffer::shm::create(kDefaultSize) could throw system exception and cause connection destruction before initilization completes. If not catch the exception on connection level, destruction will clean up unregistered resources to cause unrelated errors.

Differential Revision: D20616906

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This pull request was exported from Phabricator. Differential Revision: D20616906