Python: Modernise tornado library

python/ql/test/library-tests/web/tornado/Classes.expected

@@ -1,3 +1,4 @@
+| class DeepInheritance | test.py:23 |
 | class Handler1 | test.py:4 |
 | class Handler2 | test.py:8 |
 | class Handler3 | test.py:14 |

python/ql/test/library-tests/web/tornado/Classes.ql

@@ -4,6 +4,6 @@ import python
 import semmle.python.TestUtils
 
 import semmle.python.web.tornado.Tornado
-from ClassObject cls
+from ClassValue cls
 where cls = aTornadoRequestHandlerClass()
-select cls.toString(), remove_library_prefix(cls.getPyClass().getLocation())
+select cls.toString(), remove_library_prefix(cls.getScope().getLocation())

python/ql/test/library-tests/web/tornado/Sinks.expected

@@ -1,3 +1,4 @@
 | test.py:6 | Attribute() | externally controlled string |
 | test.py:12 | name | externally controlled string |
 | test.py:20 | url | externally controlled string |
+| test.py:26 | Attribute() | externally controlled string |

python/ql/test/library-tests/web/tornado/Sources.expected

@@ -1,3 +1,4 @@
 | test.py:6 | Attribute() | externally controlled string |
 | test.py:10 | Attribute() | [externally controlled string] |
 | test.py:17 | Attribute | tornado.request.HttpRequest |
+| test.py:26 | Attribute() | externally controlled string |

python/ql/test/library-tests/web/tornado/Taint.expected

@@ -9,3 +9,4 @@
 | test.py:19 | Subscript | externally controlled string |
 | test.py:19 | h | {externally controlled string} |
 | test.py:20 | url | externally controlled string |
+| test.py:26 | Attribute() | externally controlled string |

python/ql/test/library-tests/web/tornado/test.py

@@ -18,3 +18,9 @@ class Handler3(tornado.web.RequestHandler):
         h = req.headers
         url = h["url"]
         self.redirect(url)
+
+
+class DeepInheritance(Handler3):
+
+    def get(self):
+        self.write(self.get_argument("also_xss"))