d3d9/tests: Skip desktop window tests if device creation fails.

dlls/d3d9/tests/visual.c

@@ -26438,6 +26438,8 @@ static void test_desktop_window(void)
     device = create_device(d3d, GetDesktopWindow(), GetDesktopWindow(), TRUE);
     ok(!!device, "Failed to create a D3D device.\n");
 
+    if (device)
+    {
         hr = IDirect3DDevice9_Clear(device, 0, NULL, D3DCLEAR_TARGET, 0xffff0000, 1.0f, 0);
         ok(SUCCEEDED(hr), "Failed to clear, hr %#lx.\n", hr);
         color = getPixelColor(device, 1, 1);
@@ -26448,6 +26450,11 @@ static void test_desktop_window(void)
 
         refcount = IDirect3DDevice9_Release(device);
         ok(!refcount, "Device has %lu references left.\n", refcount);
+    }
+    else
+    {
+        skip("Failed to create a D3D device for the desktop window, skipping tests.\n");
+    }
 
     /* test device with NULL HWND */
     device = create_device(d3d, NULL, NULL, TRUE);