GitLab

Lets the test run longer (i.e. until the child actually closes its
Channel) before asserting that we receive a message from the child.

Bug: 821254
Change-Id: I629d994baf5655899dbd95177b997b97fd112e32
Reviewed-on: https://chromium-review.googlesource.com/981445
Commit-Queue: Ken Rockot <rockot@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545972}