Improve diagnostics when an elaborated-type-specifer containing a
nested-name-specifier (e.g., "class T::foo") fails to find a tag
member in the scope nominated by the
nested-name-specifier. Previously, we gave a bland

  error: 'Nested' does not name a tag member in the specified scope

which didn't actually say where we were looking, which was rather
horrible when the nested-name-specifier was instantiated. Now, we give
something a bit better:

  error: no class named 'Nested' in 'NoDepBase<T>'

llvm-svn: 100060
diff --git a/clang/test/SemaCXX/nested-name-spec.cpp b/clang/test/SemaCXX/nested-name-spec.cpp
index 8657c0d..9a611c3 100644
--- a/clang/test/SemaCXX/nested-name-spec.cpp
+++ b/clang/test/SemaCXX/nested-name-spec.cpp
@@ -64,7 +64,7 @@
 A::C c1;
 struct A::C c2;
 struct S : public A::C {};
-struct A::undef; // expected-error {{'undef' does not name a tag member in the specified scope}}
+struct A::undef; // expected-error {{no struct named 'undef' in namespace 'A'}}
 
 namespace A2 {
   typedef int INT;