Fixed #8214 -- Added back a stringification that was dropped during [8131].

This restores filtering on dates in the admin, for example. Thanks to akfarrell
and a small team of workers at the Portland Sprint.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@8494 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/backends/sqlite3/base.py

@@ -182,7 +182,7 @@ def _sqlite_extract(lookup_type, dt):
         dt = util.typecast_timestamp(dt)
     except (ValueError, TypeError):
         return None
-    return getattr(dt, lookup_type)
+    return unicode(getattr(dt, lookup_type))
 
 def _sqlite_date_trunc(lookup_type, dt):
     try: