Revert "cros: Add Attestation enrollment browser test."

This reverts commit 0cc0d519d44114a61fb9ee9231850f2588741d7b.

Reason for revert: multiple browser tests failing on chromeos. Speculatively reverting this CL as possible culprit. See crbug.com/943473

Original change's description:
> cros: Add Attestation enrollment browser test.
> 
> cryptohome and CA network communication is mocked.
> 
> Also fixes waiting for js ready in OOBE - it waits for assets
> loading.
> Also fixes certificate_based_register handling in
> policy_testserver.py
> 
> Bug: 934224, 912704
> Change-Id: Ic5816376e218436c6a2595759fa1bc9dd1b730ee
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1523099
> Reviewed-by: Pavol Marko <pmarko@chromium.org>
> Reviewed-by: Jacob Dufault <jdufault@chromium.org>
> Commit-Queue: Roman Sorokin [CET] <rsorokin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#641822}

TBR=rsorokin@chromium.org,jdufault@chromium.org,pmarko@chromium.org

Change-Id: I79194e7f2492588057cdd29fad0f9057eb92a9e3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 934224, 912704, 943473
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1529100
Reviewed-by: Alexander Hendrich <hendrich@chromium.org>
Commit-Queue: Alexander Hendrich <hendrich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#641829}
8 files changed