Revert of service worker: Don't control a subframe of an insecure context (patchset #21 id:440001 of https://codereview.chromium.org/2009453002/ )

      Reason for revert:
ServiceWorkerProviderHost::SetControllerVersionAttribute CHECK is firing in release builds: https://crbug.com/618365

Original issue's description:
> service worker: Don't control a subframe of an insecure context
>
> We must check isSecureContext when creating the network provider to
> adhere to https://w3c.github.io/webappsec/specs/powerfulfeatures/#settings-privileged.
>
> We already did this for getRegistration(), register(), unregister() but must
> also do this when deciding whether to control an in-scope document.
>
> BUG=607543
> CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_site_isolation
>
> Committed: https://crrev.com/59a2e54eeb0e61971a0c27c44c54dd0c30b5d06d
> Cr-Commit-Position: refs/heads/master@{#398229}

TBR=alexmos@chromium.org,clamy@chromium.org,horo@chromium.org,jww@chromium.org,kinuko@chromium.org,lazyboy@chromium.org,rdevlin.cronin@chromium.org,falken@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=607543

Review-Url: https://codereview.chromium.org/2055433002
Cr-Commit-Position: refs/heads/master@{#398660}