[gnome-music/wip/jfelder/3-34-scrobbler-session-key-fix] scrobbler: Do not crash if the session key is unavailable

[Jean Felder <jfelder src gnome org>]

commit 6f9ebf9e42f942d0119cee41a4bd7f56e3834a79
Author: Jean Felder <jfelder src gnome org>
Date:   Wed Oct 30 22:13:53 2019 +0100

    scrobbler: Do not crash if the session key is unavailable
    
    Related: #328
    (cherry picked from commit ea417152d542468c75ffcb183e279c44248a24e4)

 gnomemusic/scrobbler.py | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)
---
diff --git a/gnomemusic/scrobbler.py b/gnomemusic/scrobbler.py
index 6cb4e986..cefdc052 100644
--- a/gnomemusic/scrobbler.py
+++ b/gnomemusic/scrobbler.py
@@ -128,7 +128,12 @@ class GoaLastFM(GObject.GObject):
     @GObject.Property
     def session_key(self):
         """Retrieve the Last.fm session key"""
-        return self._authentication.call_get_access_token_sync(None)[0]
+        try:
+            return self._authentication.call_get_access_token_sync(None)[0]
+        except GLib.Error as e:
+            logger.warning(
+                "Error: Unable to retrieve last.fm session key", e.message)
+            return None
 
 
 class LastFmScrobbler(GObject.GObject):
@@ -160,6 +165,10 @@ class LastFmScrobbler(GObject.GObject):
         """Internal method called by self.scrobble"""
         api_key = self._goa_lastfm.client_id
         sk = self._goa_lastfm.session_key
+        if sk is None:
+            logger.warning(
+                "Error: Unable to perform last.fm api call", request_type_key)
+            return
         secret = self._goa_lastfm.secret
 
         artist = utils.get_artist_name(media)