Fix LLDB debug builds

[wallace]

Summary

A recent change in ThreadPlans introduced this little compilation error.
Seems to be related to the work around https://reviews.llvm.org/D76814.

[jingham]

Ah, great, thanks. Looks like the standalone Xcode debug build doesn't pass LDB_CONFIGURATION_DEBUG. That's a little odd, but the patch is fine.

lldb/source/Target/ThreadPlan.cpp

#endif
   return true;
 }
 
 bool ThreadPlanNull::DoPlanExplainsStop(Event *event_ptr) {
 #ifdef LLDB_CONFIGURATION_DEBUG
   fprintf(stderr,
           "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
           ", ptid = 0x%" PRIx64 ")",
-          LLVM_PRETTY_FUNCTION, m_thread.GetID(), m_thread.GetProtocolID());
+          LLVM_PRETTY_FUNCTION, GetThread().GetID(), GetThread().GetProtocolID());
 #else
   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_THREAD));
   if (log)
     log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
                ", ptid = 0x%" PRIx64 ")",
                LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
 #endif
   return true;