[valencia] Fix binding error exposed by Vala 0.25.2

[Jim Nelson <jnelson src gnome org>]

commit 48cca04f1ed5f7279e0036d4498e1575cecf02da
Author: Jim Nelson <jim yorba org>
Date:   Tue Aug 26 13:04:55 2014 -0700

    Fix binding error exposed by Vala 0.25.2

 autocomplete.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/autocomplete.vala b/autocomplete.vala
index 5dcc9c9..a13b9b5 100644
--- a/autocomplete.vala
+++ b/autocomplete.vala
@@ -34,7 +34,7 @@ class AutocompleteDialog : Object {
         window.hide();
     }
 
-    unowned string? get_completion_target(Gtk.TextBuffer buffer) {
+    string? get_completion_target(Gtk.TextBuffer buffer) {
         Gtk.TextIter start = get_insert_iter(buffer);
         Gtk.TextIter end = start;