[gnome-builder] buffer: use dzl_clear_source()

[Christian Hergert <chergert src gnome org>]

commit 807982bc2adb7edfdbcb31cc4514b8f3ecce72ce
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jan 4 02:50:52 2018 -0800

    buffer: use dzl_clear_source()

 src/libide/buffers/ide-buffer.c |    7 +------
 1 files changed, 1 insertions(+), 6 deletions(-)
---
diff --git a/src/libide/buffers/ide-buffer.c b/src/libide/buffers/ide-buffer.c
index 30ac62e..ee99ee2 100644
--- a/src/libide/buffers/ide-buffer.c
+++ b/src/libide/buffers/ide-buffer.c
@@ -815,12 +815,7 @@ ide_buffer_queue_modify_check (IdeBuffer *self)
 
   g_assert (IDE_IS_BUFFER (self));
 
-  if (priv->check_modified_timeout != 0)
-    {
-      g_source_remove (priv->check_modified_timeout);
-      priv->check_modified_timeout = 0;
-    }
-
+  dzl_clear_source (&self->check_modified_timeout);
   priv->check_modified_timeout = g_timeout_add_seconds (MODIFICATION_TIMEOUT_SECS,
                                                         do_check_modified,
                                                         self);