source-dialog: update calendar image color

After editing the color of a calendar its image is not
updated as well. Fix this by updating the image when the
edit is finished.

https://bugzilla.gnome.org/show_bug.cgi?id=773869

src/gcal-source-dialog.c

@@ -561,6 +561,31 @@ is_goa_source (GcalSourceDialog *dialog,
   return is_goa;
 }
 
+static void
+source_color_changed (GObject    *source,
+                      GParamSpec *pspec,
+                      GtkImage *icon)
+{
+  ESourceSelectable *extension;
+  GdkPixbuf *pixbuf;
+  GdkRGBA out_color;
+
+  extension = E_SOURCE_SELECTABLE (source);
+
+  if (!gdk_rgba_parse (&out_color, e_source_selectable_get_color (extension)))
+    {
+      g_warning ("Error parsing color");
+      return;
+    }
+
+  if (gdk_rgba_parse (&out_color, e_source_selectable_get_color (extension)))
+    {
+      pixbuf = get_circle_pixbuf_from_color (&out_color, 24);
+      gtk_image_set_from_pixbuf (GTK_IMAGE (icon), pixbuf);
+      g_object_unref (pixbuf);
+    }
+}
+
 static void
 invalidate_calendar_listbox_sort (GObject    *source,
                                   GParamSpec *pspec,
@@ -592,6 +617,7 @@ make_row_from_source (GcalSourceDialog *dialog,
   GdkRGBA color;
   gchar *parent_name;
 
+  ESourceSelectable *extension;
   get_source_parent_name_color (dialog->manager, source, &parent_name, NULL);
   builder = gtk_builder_new_from_resource ("/org/gnome/calendar/calendar-row.ui");
 
@@ -615,6 +641,9 @@ make_row_from_source (GcalSourceDialog *dialog,
   g_signal_connect (source, "notify::display-name", G_CALLBACK (invalidate_calendar_listbox_sort),
                     dialog->calendars_listbox);
 
+  extension = E_SOURCE_SELECTABLE (e_source_get_extension (source, E_SOURCE_EXTENSION_CALENDAR));
+  g_signal_connect (extension, "notify::color", G_CALLBACK (source_color_changed), icon);
+
   /* parent source name label */
   bottom_label = GTK_WIDGET (gtk_builder_get_object (builder, "subtitle"));
   gtk_label_set_label (GTK_LABEL (bottom_label), parent_name);