Reverted "[1.3.x] Fixed #18135 -- Close connection used for db version checking"

This reverts commit a15d3b58d8. Django
1.3.x is in security fixes only state, and this wasn't a security
issue.

django/db/backends/mysql/base.py

@@ -334,19 +334,10 @@ class DatabaseWrapper(BaseDatabaseWrapper):
 
     def get_server_version(self):
         if not self.server_version:
-            new_connection = False
             if not self._valid_connection():
-                # Ensure we have a connection with the DB by using a temporary
-                # cursor
-                new_connection = True
-                self.cursor().close()
-            server_info = self.connection.get_server_info()
-            if new_connection:
-                # Make sure we close the connection
-                self.connection.close()
-                self.connection = None
-            m = server_version_re.match(server_info)
+                self.cursor()
+            m = server_version_re.match(self.connection.get_server_info())
             if not m:
-                raise Exception('Unable to determine MySQL version from version string %r' % server_info)
+                raise Exception('Unable to determine MySQL version from version string %r' % self.connection.get_server_info())
             self.server_version = tuple([int(x) for x in m.groups()])
         return self.server_version

tests/regressiontests/backends/tests.py

@@ -56,14 +56,6 @@ class OracleChecks(unittest.TestCase):
         self.assertEqual(connection.connection.encoding, "UTF-8")
         self.assertEqual(connection.connection.nencoding, "UTF-8")
 
-class MySQLTests(TestCase):
-    @unittest.skipUnless(connection.vendor == 'mysql',
-                        "Test valid only for MySQL")
-    def test_server_version_connections(self):
-        connection.close()
-        connection.get_server_version()
-        self.assertTrue(connection.connection is None)
-
 class DateQuotingTest(TestCase):
 
     def test_django_date_trunc(self):