[gimp/gimp-2-10] Issue #4816: fix spyrogimp to work with grayscale images

[Jehan <jehanp src gnome org>]

commit 6b4f0490f5281d2fdce5367924d0a7dab53a32b9
Author: Elad Shahar <dawn ever gmail com>
Date:   Mon Mar 23 19:55:51 2020 +0200

    Issue #4816: fix spyrogimp to work with grayscale images

 plug-ins/pygimp/plug-ins/spyro_plus.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/plug-ins/pygimp/plug-ins/spyro_plus.py b/plug-ins/pygimp/plug-ins/spyro_plus.py
index 94e9d60a0f..84e5218cc6 100644
--- a/plug-ins/pygimp/plug-ins/spyro_plus.py
+++ b/plug-ins/pygimp/plug-ins/spyro_plus.py
@@ -1731,7 +1731,8 @@ class SpyroWindow(gtk.Window):
         self.engine = DrawingEngine(img, self.p)
 
         # Make a new GIMP layer to draw on
-        self.spyro_layer = gimp.Layer(img, layer_name, img.width, img.height, RGBA_IMAGE, 100, NORMAL_MODE)
+        self.spyro_layer = gimp.Layer(img, layer_name, img.width, img.height,
+                                      layer.type_with_alpha, 100, NORMAL_MODE)
         img.add_layer(self.spyro_layer, 0)
 
         self.drawing_layer = self.spyro_layer