addresses #2149 refs[t:2149] Add extra test for open db handles in ENV->db(rename|remove) to prevent race conditions in the future.
addresses #2149 refs[t:2149] Add extra test for open db handles in
ENV->db(rename|remove) to prevent race conditions in the future.

git-svn-id: b878472f12bc9c3559dea38f2e20ab86fae8ef29@15658 c7de825b-a66e-492c-adef-691d508d4ae1

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