message: Fix build for clang r291753
diff: @@ -1528,8 +1528,7 @@ ClassTemplateDecl *ClangASTContext::CreateClassTemplateDecl(
  *ast,
  decl_ctx, // What decl context do we use here? TU? The actual decl
  // context?
  - SourceLocation(), decl_name, template_param_list, template_cxx_decl,
  - nullptr);
  + SourceLocation(), decl_name, template_param_list, template_cxx_decl);
  if (class_template_decl) {
  if (access_type != eAccessNone)
  