Add test for anonymous struct containing an implicitly private data member.

Patch by Jacob Young!

llvm-svn: 300266
diff --git a/clang/test/SemaCXX/anonymous-struct.cpp b/clang/test/SemaCXX/anonymous-struct.cpp
index b584f89..bb7e6eb 100644
--- a/clang/test/SemaCXX/anonymous-struct.cpp
+++ b/clang/test/SemaCXX/anonymous-struct.cpp
@@ -21,6 +21,9 @@
   };
   static struct {
   };
+  class {
+    int anon_priv_field; // expected-error {{anonymous struct cannot contain a private data member}}
+  };
 };
 
 template <class T> void foo(T);