Fix 0f0462cacf34aa88ae71a13c4199c1b1e70f3ee6

This fails on Windows because std::future<llvm::Error> fail to compile.
Now switching to SBError as a workaround.

Failed buildbot: http://lab.llvm.org:8011/#/builders/83/builds/3021

GitOrigin-RevId: 1ac36b34db81d2fccd2b4a98d497be62083de3b1
3 files changed