GitLab

Simplify unittest callback handling in FidoBleConnection unittests

Changes OnceCallbacks to use TestCallbackReceiver.

Bug: 799044
Change-Id: Ifdad6592537490cdae8d9a8c95809db350fd4f11
Reviewed-on: https://chromium-review.googlesource.com/1011628Reviewed-by: Jan Wilken Dörrie <jdoerrie@chromium.org>
Commit-Queue: Kim Paulhamus <kpaulhamus@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550685}