Two problems with deque.__reduce__:

  1. If one of the elements is self, it ends up in args,
     which makes it impossible for the unpickler to
     correctly supply it. Fixed by using the listitems
     argument (PEP 307 says that non-lists may use this if
     they support append and extend, which deque does)
     (test_pickle_recursive). This is related to SF #1062277
     but does not depend on it.

  2. Since we wrote our reduce, the standard ones don't have
     a chance to save the instance dictionary, so we have to
     do it ourselves (TestSubclass.test_pickle).