Revert "service worker: Remove workaround for ServiceWorkerObjectHost crash."

This reverts commit 2dbd1cd14ad4f487cc373960ba9acf101477a607.

Reason for revert: The crash still exists with or without the workaround on M70. Re-adding the workaround brings M69 and M70 to the same code, so that the future fix in M70 will be easy to merge to M69.

Original change's description:
> service worker: Remove workaround for ServiceWorkerObjectHost crash.
> 
> Since issue 864731 was fixed in r576288, this workaround is no longer
> needed.
> 
> Bug: 854993
> Change-Id: I789dfb18cdb82ec51aa0ce5185586163c92269ec
> Reviewed-on: https://chromium-review.googlesource.com/1147889
> Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
> Commit-Queue: Matt Falkenhagen <falken@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#577435}

TBR=falken@chromium.org,bashi@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 854993
Change-Id: Idb68e5d11c8b14da4dfee6d2fb484cc13be72501
Reviewed-on: https://chromium-review.googlesource.com/1157665
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579673}
1 file changed