more playhead-drag/click locate debugging

libs/canvas/canvas.cc

@@ -769,6 +769,8 @@ GtkCanvas::deliver_event (GdkEvent* event)
 
 		Item* parent = item->parent ();
 
+		DEBUG_TRACE (PBD::DEBUG::CanvasEvents, string_compose ("consider delivery to %1 %2 (ignored = ? %3)\n", item->whatami(), item->name.empty() ? "[unknown]" : item->name, item->ignore_events()));
+
 		if (!item->ignore_events () &&
 		    item->Event (event)) {
 			/* this item has just handled the event */
@@ -1483,4 +1485,3 @@ GtkCanvasViewport::on_size_request (Gtk::Requisition* req)
 	req->width = 16;
 	req->height = 16;
 }
-