[orca] Use gi.require_version to address PyGIWarning

[Joanmarie Diggs <joanied src gnome org>]

commit 9376d33700ffd117b7b3c98a1c5f23a72b1a763f
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Aug 14 10:15:28 2015 -0400

    Use gi.require_version to address PyGIWarning

 src/orca/mouse_review.py |    3 +++
 src/orca/orca.py         |    6 ++++++
 2 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/src/orca/mouse_review.py b/src/orca/mouse_review.py
index 3871804..f99165d 100644
--- a/src/orca/mouse_review.py
+++ b/src/orca/mouse_review.py
@@ -25,9 +25,12 @@ __date__      = "$Date$"
 __copyright__ = "Copyright (c) 2008 Eitan Isaacson"
 __license__   = "LGPL"
 
+import gi
+
 from . import debug
 
 try:
+    gi.require_version("Wnck", "3.0")
     from gi.repository import Wnck
     _mouseReviewCapable = True
 except:
diff --git a/src/orca/orca.py b/src/orca/orca.py
index b86ea3e..2238939 100644
--- a/src/orca/orca.py
+++ b/src/orca/orca.py
@@ -29,6 +29,7 @@ __copyright__ = "Copyright (c) 2004-2009 Sun Microsystems Inc." \
                 "Copyright (c) 2012 Igalia, S.L."
 __license__   = "LGPL"
 
+import gi
 import importlib
 import os
 import pyatspi
@@ -49,10 +50,15 @@ try:
     # for this is to allow "orca --text-setup" to work even if
     # the desktop is not running.
     #
+    gi.require_version("Gtk", "3.0")
     from gi.repository import Gtk
+
+    gi.require_version("Gdk", "3.0")
     from gi.repository import Gdk
+
     # Note: This last import is here due to bgo #673396.
     # See bgo#673397 for the rest of the story.
+    gi.require_version("GdkX11", "3.0")
     from gi.repository.GdkX11 import X11Screen
 except:
     pass