[pygobject] pygi-source: clear exceptions in finalize handler

[Christoph Reiter <creiter src gnome org>]

commit c39bf20cca3d1c6bcf89f93759772117d087b042
Author: Christoph Reiter <creiter src gnome org>
Date:   Sat Apr 1 17:49:01 2017 +0200

    pygi-source: clear exceptions in finalize handler
    
    This was executed in the context of Source.__del__ and while Python
    ignores errors there it started to warn with Python 3.
    
    This fixes the warnings visible when running test_source under Python 3.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=780812

 gi/pygi-source.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gi/pygi-source.c b/gi/pygi-source.c
index e84c25e..5305260 100644
--- a/gi/pygi-source.c
+++ b/gi/pygi-source.c
@@ -165,6 +165,8 @@ pyg_source_finalize(GSource *source)
        } else {
            Py_DECREF(t);
        }
+    } else {
+        PyErr_Clear ();
     }
 
     PyGILState_Release(state);