Correctly initialize monitors for 32-bit

Fully initialize lock_owner... fields. The only one that's critical
here is the lock_owner_ field itself, but let's be consistent.

A randomly set lock_owner_ field can cause GetLockOwnerInfo() to
spin indefinitely.

Bug: 148094637
Test: TreeHugger
Change-Id: I50cab5ba412a2a8113e44c5f05c2990c5d7d101f
1 file changed