GitLab

* Refactors the callback check out of EndTest

Bug: 974078
Change-Id: Ie34b18d9ea09a0b5039acf74f32d24de98efa784
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1663415Reviewed-by: Max Morin <maxmorin@chromium.org>
Commit-Queue: Evan Shrubsole <eshr@google.com>
Cr-Commit-Position: refs/heads/master@{#670053}