[orca] Add a missing check that gstreamer is available

[Joanmarie Diggs <joanied src gnome org>]

commit b0ae3a9acd232f3e249286741f9e38330ec26442
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Feb 26 16:42:45 2016 -0500

    Add a missing check that gstreamer is available

 src/orca/sound.py |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/orca/sound.py b/src/orca/sound.py
index 39df4c5..4f8cad5 100644
--- a/src/orca/sound.py
+++ b/src/orca/sound.py
@@ -104,6 +104,9 @@ class Player:
         if self._initialized:
             return
 
+        if not _gstreamerAvailable:
+            return
+
         self._player = Gst.ElementFactory.make('playbin', 'player')
         bus = self._player.get_bus()
         bus.add_signal_watch()