Put new warning in r159965 under a flag to appease buildbots.  Someone please
verify this is the correct grouping.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159966 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 52641b8..bf5e3ac 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -5524,7 +5524,8 @@
   "invalid conversion between ext-vector type %0 and %1">;
 
 def warn_duplicate_attribute : Warning<
-  "attribute %0 is already applied with different parameters">;
+  "attribute %0 is already applied with different parameters">,
+  InGroup<IgnoredAttributes>;
 
 // Type
 def ext_invalid_sign_spec : Extension<"'%0' cannot be signed or unsigned">;