SmbService: Ensure DBusThreadManager is initialized before Get()

Prevents an issue once enabling SMB by default where the SmbService
ctor runs before the DBusThreadManager is properly initialized. This
only happens during tests.

Bug: chromium:757625
Change-Id: Id25265a7a9b763c5ea1ab59106df366dda4fd309
Reviewed-on: https://chromium-review.googlesource.com/1195644
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587298}
1 file changed