Fix content type for qpid notifier.

Fix bug 980872.

This patch fixes a regression I introduced in
2d36fac.  In that patch, I adjusted the
content_type for messages sent with the qpid notifier to be
'application/json' to match a change that went into the kombu notifier.
Unfortunately, it's wrong.

I assumed based on the kombu change that notifications were being json
encoded before being passed into the notification driver.  That's not
the case.  The message is a dict.  So, just revert the change to set the
content_type and let Qpid encode the notification as 'amqp/map'.

Change-Id: Iea027409f6200109b97fed93073cff84bc915536

glance/notifier/notify_qpid.py

@@ -135,16 +135,13 @@ def _sender(self, priority):
         return self.session.sender(address)
 
     def warn(self, msg):
-        qpid_msg = qpid.messaging.Message(content=msg,
-                                          content_type='application/json')
+        qpid_msg = qpid.messaging.Message(content=msg)
         self.sender_warn.send(qpid_msg)
 
     def info(self, msg):
-        qpid_msg = qpid.messaging.Message(content=msg,
-                                          content_type='application/json')
+        qpid_msg = qpid.messaging.Message(content=msg)
         self.sender_info.send(qpid_msg)
 
     def error(self, msg):
-        qpid_msg = qpid.messaging.Message(content=msg,
-                                          content_type='application/json')
+        qpid_msg = qpid.messaging.Message(content=msg)
         self.sender_error.send(qpid_msg)

glance/tests/unit/test_notifier.py

@@ -316,7 +316,7 @@ def tearDown(self):
         super(TestQpidNotifier, self).tearDown()
 
     def _test_notify(self, priority):
-        test_msg = json.dumps({'a': 'b'})
+        test_msg = {'a': 'b'}
 
         self.mock_connection = self.mocker.CreateMock(self.orig_connection)
         self.mock_session = self.mocker.CreateMock(self.orig_session)