[gimp] app: use new gimp_tools_blink_widget() to blink source scrolldown.

[Jehan <jehanp src gnome org>]

commit e1c3e7d85be69f1c7241db678de1ed1fc2451706
Author: Jehan <jehan girinstud io>
Date:   Fri Mar 4 15:41:53 2022 +0100

    app: use new gimp_tools_blink_widget() to blink source scrolldown.
    
    When the bucket fill can't work because the line art source is not
    right, let's blink the associated settings for people to know where to
    look at.

 app/tools/gimpbucketfilltool.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/app/tools/gimpbucketfilltool.c b/app/tools/gimpbucketfilltool.c
index 44c3752bb7..a507c51668 100644
--- a/app/tools/gimpbucketfilltool.c
+++ b/app/tools/gimpbucketfilltool.c
@@ -632,6 +632,8 @@ gimp_bucket_fill_tool_button_press (GimpTool            *tool,
     {
       gimp_tool_message_literal (tool, display,
                                  _("No valid line art source selected."));
+      gimp_tools_blink_widget (display->gimp,
+                               "gimp-tool-options", "line-art-source");
       return;
     }