tests: Fix some func tests to do with metadata maximums

Previously, if a cluster's combined configured max_meta_name_length and
max_meta_value_length constraints were larger than the configured
max_meta_overall_size, we would accidentally go over the overall size
while intending to just test being exactly at the value length-limit.

Change-Id: I42a5287011509e5b43959aab060f9ec7405ae5b9

test/functional/test_account.py

@@ -796,6 +796,14 @@ class TestAccount(unittest.TestCase):
                          'k' * self.max_meta_name_length): 'v'})
         resp.read()
         self.assertEqual(resp.status, 204)
+        # Clear it, so the value-length checking doesn't accidentally trip
+        # the overall max
+        resp = retry(post,
+                     {'X-Account-Meta-' + (
+                         'k' * self.max_meta_name_length): ''})
+        resp.read()
+        self.assertEqual(resp.status, 204)
+
         resp = retry(
             post,
             {'X-Account-Meta-' + ('k' * (

test/functional/test_container.py

@@ -407,6 +407,13 @@ class TestContainer(unittest.TestCase):
             {'X-Container-Meta-' + ('k' * self.max_meta_name_length): 'v'})
         resp.read()
         self.assertEqual(resp.status, 204)
+        # Clear it, so the value-length checking doesn't accidentally trip
+        # the overall max
+        resp = retry(
+            post,
+            {'X-Container-Meta-' + ('k' * self.max_meta_name_length): ''})
+        resp.read()
+        self.assertEqual(resp.status, 204)
         resp = retry(
             post,
             {'X-Container-Meta-' + (