Warnings cleanup patch from Jean-Daniel Dupas.

llvm-svn: 109226
diff --git a/lldb/source/Target/Thread.cpp b/lldb/source/Target/Thread.cpp
index fe9f7f5..2cf64d1 100644
--- a/lldb/source/Target/Thread.cpp
+++ b/lldb/source/Target/Thread.cpp
@@ -938,7 +938,7 @@
     {
         thread_plan_sp.reset(new ThreadPlanStepThrough (*this, stop_other_threads));
         if (thread_plan_sp && !thread_plan_sp->ValidatePlan (NULL))
-            return false;
+            return NULL;
     }
     QueueThreadPlan (thread_plan_sp, abort_other_plans);
     return thread_plan_sp.get();