[gtk/gles-win32] inspector/general.c: Check whether GL context supports WGL

[Chun-wei Fan <fanchunwei src gnome org>]

commit 89d87e34827ff6d954cbc45b8e9e42b4ec17a987
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Wed Mar 30 10:23:49 2022 +0800

    inspector/general.c: Check whether GL context supports WGL
    
    We may well be using an EGL context that does not support Desktop (W)GL on
    Windows, such as in the case of using libANGLE.  So, check whether WGL is
    supported for this running instance before trying to query WGL extensions.
    
    This will get rid of warning messages from libepoxy.

 gtk/inspector/general.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/gtk/inspector/general.c b/gtk/inspector/general.c
index ad52422fa3..f456ea0da4 100644
--- a/gtk/inspector/general.c
+++ b/gtk/inspector/general.c
@@ -45,12 +45,12 @@
 
 #ifdef GDK_WINDOWING_WIN32
 #include "win32/gdkwin32.h"
+#include "gdkglcontextprivate.h"
 #include <epoxy/wgl.h>
-#endif
-
 #ifdef GDK_WIN32_ENABLE_EGL
 #include <epoxy/egl.h>
 #endif
+#endif
 
 #ifdef GDK_WINDOWING_MACOS
 #include "macos/gdkmacos.h"
@@ -387,7 +387,8 @@ init_gl (GtkInspectorGeneral *gen)
   else
 #endif
 #ifdef GDK_WINDOWING_WIN32
-  if (GDK_IS_WIN32_DISPLAY (gen->display))
+  if (GDK_IS_WIN32_DISPLAY (gen->display) &&
+      gdk_gl_backend_can_be_used (GDK_GL_WGL, NULL))
     {
       int gl_version;
       char *version;