Revert "[DL]: Ensure to reject update/commit promises on disconnected elements."

This reverts commit 5f4ce97e16f4a7c1d57f5685ad230923285cf549.

Reason for revert: On https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Linux%20Tests%20%28dbg%29%281%29?limit=200, virtual/display-lock/display-lock/lock-before-append/acquire-update-measure-remove.html has been failing about 90% of the time since this landed.

Original change's description:
> [DL]: Ensure to reject update/commit promises on disconnected elements.
> 
> This patch ensures that we reject update/commit when it happens on
> a disconnected element.
> 
> R=​chrishtr@chromium.org
> 
> Bug: 882663
> Change-Id: Iaee923a4f41714b437c0a2b85bbb175359a2f32c
> Reviewed-on: https://chromium-review.googlesource.com/c/1387944
> Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
> Commit-Queue: Chris Harrelson <chrishtr@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#618713}

TBR=vmpstr@chromium.org,chrishtr@chromium.org

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

Bug: 882663
Change-Id: I491a3f7db511a69f2538e3158bc4666c6f9eaf85
Reviewed-on: https://chromium-review.googlesource.com/c/1390433
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#618847}
6 files changed