Add missing license headers

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@258196 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/support/disable_missing_braces_warning.h b/test/support/disable_missing_braces_warning.h
index 967a87a..97fd8a8 100644
--- a/test/support/disable_missing_braces_warning.h
+++ b/test/support/disable_missing_braces_warning.h
@@ -1,3 +1,11 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
 #ifndef SUPPORT_DISABLE_MISSING_BRACES_WARNING_H
 #define SUPPORT_DISABLE_MISSING_BRACES_WARNING_H