Revert 180829 as it causes hangs in TestTypeCompletion.py on 2 Linux buildbots:

http://lab.llvm.org:8011/builders/lldb-x86_64-linux/builds/3810
http://lab.llvm.org:8011/builders/lldb-x86_64-debian-clang/builds/2754



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@180870 91177308-0d34-0410-b5e6-96231b3b80d8