shelve: use listdir() instead of readdir() when we don't need stat information Differential Revision: https://phab.mercurial-scm.org/D9737

shelve: don't crash on file with unexpected extension in .hg/shelved/ We assumed that the files in the `.hg/shelved/` directory have an extension. That's a valid assumption except that users may put garbage in the directory. This patch fixes the crash by simply not assuming that the result of splittin a string at '.' yields an extension. We don't use the extension since the previous patch anyway. Differential Revision: https://phab.mercurial-scm.org/D9720