tree e80d127cc246fdc41177ad8e25148eb0f6ddbc33
parent 6c23d7e5f818063e12ad243b07d2ffbbc709f489
author radokirov <radokirov@google.com> 1552004857 -0800
committer Copybara-Service <copybara-worker@google.com> 1552413798 -0700

Upgrade to compile with TS 3.3.3333

ts.compilerHost.getDirectories is now an optional field, so wrap access in a
nullablity check.

PiperOrigin-RevId: 237350326