These tests rely on THR_KEY_mysys but it is not initialized. On
Linux, the corresponding thread variable is null, but on macOS it has a
nonzero value. In all cases, initialize the variable explicitly by
calling MY_INIT and my_end appropriately.
Cleanup unnecessary whitespace at the end of lines and end of files
in the unittest/ directory. Note that all code changes are
non-functional.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.