The control flow in __wt_conn_dhandle_close is complex and subtle - we've made previous attempts to simplify it and introduced bugs (see below). We should revisit and clarify.

In WT-4339 (and possibly WT-4334 and WT-4358) we determined that some changes from WT-4314 caused a variety of test failures. We have reverted part of that change. Specifically the change in this commit https://github.com/wiredtiger/wiredtiger/pull/4287/commits/1a10c6606fe49c24c6874054a21ecd9ce9e93cd9 causes the failures. This change was supposed to be a simplification.

We should dissect this change more and figure out what is causing the problem.