In preparation for factoring persistent variables into a generic part and a
Clang-specific part, create the ExpressionVariable source/header file and
move ClangExpressionVariable into the Clang expression parser plugin.

It is expected that there are some ugly #include paths... these will be resolved
by either (1) making that code use generic expression variables (once they're
separated appropriately) or (2) moving that code into a plug-in, often
the expression parser plug-in.

llvm-svn: 246737
diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index 96ba0b3..307070b 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -35,7 +35,7 @@
 #include "lldb/DataFormatters/StringPrinter.h"
 #include "lldb/DataFormatters/ValueObjectPrinter.h"
 
-#include "lldb/Expression/ClangExpressionVariable.h"
+#include "lldb/../../source/Plugins/ExpressionParser/Clang/ClangExpressionVariable.h"
 #include "lldb/Expression/ClangPersistentVariables.h"
 
 #include "lldb/Host/Endian.h"