Don't try to use "OkayToDiscard" to mean BOTH this plan is a user plan or not AND unwind on error.

rdar://problem/11419156


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@156627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Target/ThreadPlanCallUserExpression.cpp b/source/Target/ThreadPlanCallUserExpression.cpp
index b46d6b4..f739d2a 100644
--- a/source/Target/ThreadPlanCallUserExpression.cpp
+++ b/source/Target/ThreadPlanCallUserExpression.cpp
@@ -47,6 +47,9 @@
     ThreadPlanCallFunction (thread, function, ClangASTType(), arg, stop_other_threads, discard_on_error, this_arg, cmd_arg),
     m_user_expression_sp (user_expression_sp)
 {
+    // User expressions are generally "User generated" so we should set them up to stop when done.
+    SetIsMasterPlan (true);
+    SetOkayToDiscard(false);
 }
 
 ThreadPlanCallUserExpression::~ThreadPlanCallUserExpression ()