Add another failing test for 412 logging

I tried to move res.fix_conditional_response() into the get_log_line
method in utils but couldn't find a container request that was
*actually* conditional.  We return 412 from the container on a couple
of bad requests where we really probably shouldn't - but regardless those
responses aren't really conditional.

Plus I'd have to make a synthetic test in utils somewhere.

So this seems better - leave the fix closer to the problem.

Change-Id: I76237d5d5025a653e879141b03df863205c59f3a
Related-Change-Id: I66c871f1f15fb43f19d59331b05cc7567ce10063

test/unit/obj/test_server.py

@@ -2857,6 +2857,15 @@ class TestObjectController(unittest.TestCase):
         self.assertEqual(resp.status_int, 200)
         self.assertEqual(resp.etag, etag)
 
+        req = Request.blank(
+            '/sda1/p/a/c/o', environ={'REQUEST_METHOD': 'HEAD'},
+            headers={'If-Match': '"11111111111111111111111111111111"'})
+        resp = req.get_response(self.object_controller)
+        self.assertEqual(resp.status_int, 412)
+        self.assertIn(
+            '"HEAD /sda1/p/a/c/o" 412 - ',
+            self.object_controller.logger.get_lines_for_level('info')[-1])
+
         req = Request.blank(
             '/sda1/p/a/c/o', environ={'REQUEST_METHOD': 'GET'},
             headers={'If-Match': '"11111111111111111111111111111111"'})