Fix test_iterlen by returning the iterator of dict views. Problem is that

Fix test_iterlen by returning the iterator of dict views.  Problem is that
iteritems and itervalues' previous object were both an iterator *and* and
iterable.  The tests expected an iterator but were given an iterable.

Should the 2to3 conversion for iter(values|items|keys) change the code to
``iter(dict.keys())`` to be more compatible?