Avoid spurious WINRT_NATVIS redefinition warning (#1044)

oldnewthing · web-flow · commit 2d9ed4e308f7 · 2021-10-21T09:52:05.000-07:00
diff --git a/strings/base_natvis.h b/strings/base_natvis.h
@@ -1,5 +1,5 @@
 
-#ifdef _DEBUG
+#if defined(_DEBUG) && !defined(WINRT_NATVIS)
 #define WINRT_NATVIS
 #endif
 
