Microsoft's __uuidof operator returns a lvalue.

llvm-svn: 122021
diff --git a/clang/lib/AST/ExprClassification.cpp b/clang/lib/AST/ExprClassification.cpp
index 05d175c..4cf393d 100644
--- a/clang/lib/AST/ExprClassification.cpp
+++ b/clang/lib/AST/ExprClassification.cpp
@@ -303,7 +303,7 @@
   }
       
   case Expr::CXXUuidofExprClass:
-    return Cl::CL_PRValue;
+    return Cl::CL_LValue;
   }
   
   llvm_unreachable("unhandled expression kind in classification");