Timeout if device isn't mounted.

If the invoked FUSE binary fails to mount the requested filesystem,
the dev_t won't actually change.  To avoid getting waiting forever
and triggering the watchdog, timeout after 5 seconds.

Test: manually hang after fork and verify that we timeout
Bug: 65756209
Change-Id: I6ea5fd08ed14c72c1d7f7064bfd0d9ac81d4897b
2 files changed