bpo-36492: Deprecate passing some arguments as keyword arguments. (GH-12637)

Deprecated passing the following arguments as keyword arguments:

- "func" in functools.partialmethod(), weakref.finalize(),
  profile.Profile.runcall(), cProfile.Profile.runcall(),
  bdb.Bdb.runcall(), trace.Trace.runfunc() and
  curses.wrapper().
- "function" in unittest.addModuleCleanup() and
  unittest.TestCase.addCleanup().
- "fn" in the submit() method of concurrent.futures.ThreadPoolExecutor
  and concurrent.futures.ProcessPoolExecutor.
- "callback" in contextlib.ExitStack.callback(),
  contextlib.AsyncExitStack.callback() and
  contextlib.AsyncExitStack.push_async_callback().
- "c" and "typeid" in the create() method of multiprocessing.managers.Server
  and multiprocessing.managers.SharedMemoryServer.
- "obj" in weakref.finalize().

Also allowed to pass arbitrary keyword arguments (even "self" and "func")
if the above arguments are passed as positional argument.

Lib/test/test_concurrent_futures.py

@@ -49,6 +49,9 @@ INITIALIZER_STATUS = 'uninitialized'
 def mul(x, y):
     return x * y
 
+def capture(*args, **kwargs):
+    return args, kwargs
+
 def sleep_and_raise(t):
     time.sleep(t)
     raise Exception('this is an exception')
@@ -658,6 +661,13 @@ class ExecutorTest:
     def test_submit_keyword(self):
         future = self.executor.submit(mul, 2, y=8)
         self.assertEqual(16, future.result())
+        future = self.executor.submit(capture, 1, self=2, fn=3)
+        self.assertEqual(future.result(), ((1,), {'self': 2, 'fn': 3}))
+        with self.assertWarns(DeprecationWarning):
+            future = self.executor.submit(fn=capture, arg=1)
+        self.assertEqual(future.result(), ((), {'arg': 1}))
+        with self.assertRaises(TypeError):
+            self.executor.submit(arg=1)
 
     def test_map(self):
         self.assertEqual(