[gtk+] gtk-demo: Fix up some warnings

[Matthias Clasen <matthiasc src gnome org>]

commit 2fd984987d1f66a01f0667aad461fdea5963af4c
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Jun 19 22:47:57 2016 -0400

    gtk-demo: Fix up some warnings
    
    The search entry example was a bit sloppy in cleaning up its
    sources, causing warnings.

 demos/gtk-demo/search_entry.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)
---
diff --git a/demos/gtk-demo/search_entry.c b/demos/gtk-demo/search_entry.c
index 67a10b5..8573aa1 100644
--- a/demos/gtk-demo/search_entry.c
+++ b/demos/gtk-demo/search_entry.c
@@ -43,8 +43,11 @@ static gboolean
 finish_search (GtkButton *button)
 {
   show_find_button ();
-  g_source_remove (search_progress_id);
-  search_progress_id = 0;
+  if (search_progress_id)
+    {
+      g_source_remove (search_progress_id);
+      search_progress_id = 0;
+    }
   return G_SOURCE_REMOVE;
 }
 
@@ -71,7 +74,11 @@ static void
 stop_search (GtkButton *button,
              gpointer   data)
 {
-  g_source_remove (finish_search_id);
+  if (finish_search_id)
+    {
+      g_source_remove (finish_search_id);
+      finish_search_id = 0;
+    }
   finish_search (button);
 }