Remove a deadlock condition.  A bit of explanation is needed: When calling  ThreadCancel in Host::WillTerminate g_monitor_thread may be blocked on a call to pthread_cond_wait (for example, line 640).  Now, by default, when a  cancellation request is serviced g_monitor_thread will again own the mutex guarding the condition variable it was waiting on.  This causes the call to  SetValue in Host::WillTerminate to hit a deadlock.
Remove a deadlock condition.  A bit of explanation is needed: When calling 
ThreadCancel in Host::WillTerminate g_monitor_thread may be blocked on a call
to pthread_cond_wait (for example, line 640).  Now, by default, when a 
cancellation request is serviced g_monitor_thread will again own the mutex
guarding the condition variable it was waiting on.  This causes the call to 
SetValue in Host::WillTerminate to hit a deadlock.

The call to SetValue does not appear to be needed, so removing it solves
the issue.

Patch from Stephen Wilson.



git-svn-id: b33bab8abb5b18c12ee100cd7761ab452d00b2b0@109228 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb