Fixing whitespace problems

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@111755 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/containers/stack_allocator.h b/test/containers/stack_allocator.h
index 4d3426b..30f5871 100644
--- a/test/containers/stack_allocator.h
+++ b/test/containers/stack_allocator.h
@@ -49,4 +49,4 @@
 void
 swap(stack_allocator<T, N>& x, stack_allocator<T, N>& y) {}
 
-#endif
+#endif  // STACK_ALLOCATOR_H