Fix locking of libnativeloader

This commit fixes race condition introduced in
d047c925af62e1fe28fcd1c1940df4afe18d458a

Bug: http://b/27189432
Bug: http://b/22548808
Change-Id: I5d94f130937f18d3443878b3521715a8f87427e0
(cherry picked from commit 34d5a20c8bb57adae8711c7f9d90a77fbd4043c7)
1 file changed