Fix Deadlock Issue On AppFuseBridge

There are two locks used by AppFuseBridge.
First is it's object lock, and the second is a mutex lock in app fuse library.
There are two oppsite routines to get those locks.

  (Thread A) Got Java lock -> Try to get Native lock
  (Thread B)        Got Native lock -> Try to get Java lock

The order must be followed to obtain two locks.
If not, the dead lock will be caused.
Therefore we change the routine to get the mutex lock first, and the object lock later.

Signed-off-by: hyeeun.jun@samsung.com <hyeeun.jun@samsung.com>
Bug: https://issuetracker.google.com/issues/145707568
Bug: 157535024
Test: atest --test-mapping apex/blobstore

Change-Id: I1f05cc98953d8452147370dd04c223d54c0e5362