Add timeout expectation for service-workers-force-update-on-page-load.js

Bug: 847373
Change-Id: I6a370c3be5b84343fec9a6be6b4c8d1fa305f8ac
No-Try: true
Tbr: chenwilliam@chromium.org, horo@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/1076867
Commit-Queue: Adithya Srinivasan <adithyas@chromium.org>
Reviewed-by: Adithya Srinivasan <adithyas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#562965}
1 file changed