bpo-38525: Fix a segmentation fault when using reverse iterators of empty dict (GH-16846)


The reverse iterator for empty dictionaries was not handling correctly shared-key dictionaries.
(cherry picked from commit 24dc2f8c56697f9ee51a4887cf0814b6600c1815)

Co-authored-by: Dong-hee Na <donghee.na92@gmail.com>
3 files changed