QDict: Fix size update

Key replacement should not update the dictionary's size.

This commit also adds a test for the bug.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

check-qdict.c

@@ -205,6 +205,8 @@ START_TEST(qdict_put_exists_test)
 
     value = qdict_get_int(tests_dict, key);
     fail_unless(value == 2);
+
+    fail_unless(qdict_size(tests_dict) == 1);
 }
 END_TEST
 

qdict.c

@@ -122,9 +122,8 @@ void qdict_put_obj(QDict *qdict, const char *key, QObject *value)
         /* allocate a new entry */
         entry = alloc_entry(key, value);
         QLIST_INSERT_HEAD(&qdict->table[hash], entry, next);
+        qdict->size++;
     }
-
-    qdict->size++;
 }
 
 /**