app: don't invalidate all images on color config changes

Now all previews and the display shell connect to the color config
itself, there is no need any longer to connect to the global color
config's "notify" any longer from GimpImage. Also, the settings there
are for display purposes only, so nothing in the image itself needs
to be notified of the config change.

app/core/gimpimage.c

@@ -848,10 +848,6 @@ gimp_image_constructed (GObject *object)
                            G_CALLBACK (gimp_viewable_size_changed),
                            image, G_CONNECT_SWAPPED);
 
-  g_signal_connect_object (config->color_management, "notify",
-                           G_CALLBACK (gimp_color_managed_profile_changed),
-                           image, G_CONNECT_SWAPPED);
-
   gimp_container_add (image->gimp->images, GIMP_OBJECT (image));
 }