Remove some now-incorrect and now-obsolete DCHECKs.
~Mutex already checks that the mutex isn't locked, and already has an
exception for the case where we're shutting down.
diff --git a/src/monitor.cc b/src/monitor.cc
index a29f2a1..c4deccb 100644
@@ -123,13 +123,6 @@
DCHECK(obj_ != NULL);
- // This lock is associated with an object that's being swept.
- bool locked = lock_.TryLock();
- DCHECK(locked) << obj_;