Prior to adding the new "expected-no-diagnostics" directive to VerifyDiagnosticConsumer, make the necessary adjustment to 580 test-cases which will henceforth require this new directive.

llvm-svn: 166280
diff --git a/clang/test/Parser/cxx-attributes.cpp b/clang/test/Parser/cxx-attributes.cpp
index 8603b30..5ea0ce2 100644
--- a/clang/test/Parser/cxx-attributes.cpp
+++ b/clang/test/Parser/cxx-attributes.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
+// expected-no-diagnostics
 
 class c {
   virtual void f1(const char* a, ...)