Because thread_ object is created in Init, destructor used to crash when
calling thread_->Stop() because it was referencing a null pointer.
Bug: webrtc:9404
Change-Id: I1c943d0fa50f9341aaa516b32495bb25bf4d664b
Reviewed-on: https://webrtc-review.googlesource.com/84122
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23682}
a97c931cba