This reverts commit d3d13e4b.

Reason for revert: Makes an incorrect assumption.

Original change's description:
> [turbofan] Improve UpdateType debug output.
> 
> R=​jarin@chromium.org
> 
> Bug: chromium:906567
> Change-Id: Ic99c7a240ecb37c7b032b388f604d3f256d335b3
> Reviewed-on: https://chromium-review.googlesource.com/c/1392196
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Commit-Queue: Georg Neis <neis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58497}

TBR=jarin@chromium.org,neis@chromium.org

Change-Id: I1bfc6d38f1c6cb67ef403d8be84070aa2c0effb6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:906567
Reviewed-on: https://chromium-review.googlesource.com/c/1394546Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58519}