[latexila] Don't use gtk_source_completion_info_set_widget() (deprecated)

[SÃbastien Wilmet <swilmet src gnome org>]

commit 0fc2df83d84c6702f0eff7636a9ea28de27eda44
Author: SÃbastien Wilmet <swilmet gnome org>
Date:   Sun Jan 27 18:48:33 2013 +0100

    Don't use gtk_source_completion_info_set_widget() (deprecated)
    
    Use gtk_container_add() instead.
    
    It has been deprecated recently in GtkSourceView, so the master branch
    is required for now.

 configure.ac        |    2 +-
 src/completion.vala |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 9ab0b90..6682a29 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,7 @@ LT_INIT
 # Required dependencies versions
 GLIB_REQUIRED_VERSION="2.32"
 GTK_REQUIRED_VERSION="3.6.0"
-GTKSOURCEVIEW_REQUIRED_VERSION="3.4.1"
+GTKSOURCEVIEW_REQUIRED_VERSION="3.7.3"
 VALA_REQUIRED_VERSION="0.18.0.82"
 
 AC_SUBST([GLIB_REQUIRED_VERSION])
diff --git a/src/completion.vala b/src/completion.vala
index 5c0fe31..e21069c 100644
--- a/src/completion.vala
+++ b/src/completion.vala
@@ -304,7 +304,7 @@ public class CompletionProvider : GLib.Object, SourceCompletionProvider
     {
         _calltip_window = new SourceCompletionInfo ();
         _calltip_window_label = new Label (null);
-        _calltip_window.set_widget (_calltip_window_label);
+        _calltip_window.add (_calltip_window_label);
     }
 
     // Show the LaTeX command prototype, with the current argument in bold.