plug-ins: improve default color handling of foggify

- To set color values in the 0-255 range we now have to use set_uchar.
- Because setting a default color is not working, the color in config
  could be None, which if the color wasn't changed caused a CRITICAL.

Let's check for None and if that is the case then manually set our
default color.

plug-ins/python/foggify.py

@@ -28,8 +28,19 @@ import sys
 def N_(message): return message
 def _(message): return GLib.dgettext(None, message)
 
+_color = Gimp.RGB()
+_color.set_uchar(240, 0, 0)
+_color.set_alpha(1.0)
 
 def foggify(procedure, run_mode, image, n_drawables, drawables, config, data):
+    # Work around not being able to set default color by only setting it
+    # when color in our config is None. This won't help when resetting to
+    # factory default. This also fixes a critical when running without
+    # changing the color away from None.
+    color = config.get_property('color')
+    if color is None:
+        config.set_property('color', _color)
+
     if run_mode == Gimp.RunMode.INTERACTIVE:
         GimpUi.init('python-fu-foggify')
         dialog = GimpUi.ProcedureDialog(procedure=procedure, config=config)
@@ -89,9 +100,6 @@ def foggify(procedure, run_mode, image, n_drawables, drawables, config, data):
 
     return procedure.new_return_values(Gimp.PDBStatusType.SUCCESS, GLib.Error())
 
-_color = Gimp.RGB()
-_color.set(240.0, 0, 0)
-
 class Foggify (Gimp.PlugIn):
     ## Parameters ##
     __gproperties__ = {