Revert of Enable viewer in non-Vulkan builds

tools/viewer/sk_app/win/Window_win.cpp

Index: tools/viewer/sk_app/win/Window_win.cpp
diff --git a/tools/viewer/sk_app/win/Window_win.cpp b/tools/viewer/sk_app/win/Window_win.cpp
index 03537caa45cac182304cecc01ffd97bce29e9681..f9762a8787be98038e0d38a4a2d6eadd9a628bbf 100644
--- a/tools/viewer/sk_app/win/Window_win.cpp
+++ b/tools/viewer/sk_app/win/Window_win.cpp
@@ -13,9 +13,7 @@
 
 #include "SkUtils.h"
 #include "../GLWindowContext.h"
-#ifdef SK_VULKAN
 #include "../VulkanWindowContext.h"
-#endif
 
 namespace sk_app {
 
@@ -277,11 +275,10 @@
         default:
             fWindowContext = GLWindowContext::Create((void*)&platformData, params);
             break;
-#ifdef SK_VULKAN
+
         case kVulkan_BackendType:
             fWindowContext = VulkanWindowContext::Create((void*)&platformData, params);
             break;
-#endif
     }
 
     return (SkToBool(fWindowContext));