Now persistent expression data no longer lives with the Target, but rather with
the corresponding TypeSystem.  This makes sense because what kind of data there
is -- and how it can be looked up -- depends on the language.

Functionality that is common to all type systems is factored out into
PersistentExpressionState.

llvm-svn: 248934
diff --git a/lldb/source/API/SBFrame.cpp b/lldb/source/API/SBFrame.cpp
index 5862b95..57572f8 100644
--- a/lldb/source/API/SBFrame.cpp
+++ b/lldb/source/API/SBFrame.cpp
@@ -956,7 +956,7 @@
                 case eValueTypeConstResult:         // constant result variables
                     {
                         ConstString const_name(name);
-                        ExpressionVariableSP expr_var_sp (target->GetPersistentVariables().GetVariable (const_name));
+                        ExpressionVariableSP expr_var_sp (target->GetPersistentVariable (const_name));
                         if (expr_var_sp)
                         {
                             value_sp = expr_var_sp->GetValueObject();