Add a missing break, from John Wiegley

llvm-svn: 126919
diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 8474ea3..45653e6 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -2176,6 +2176,7 @@
       Diags.Report(DiagID);
       return;
     }
+    break;
   }
   }
 }