Revert "Reland CHECKs that verify bookmark USS invariants"

This reverts commit b3a6bf68329788906042be48cd89c49189c4b6df.

Reason for revert: crashes observed in 73.0.3642.0 canary.

Original change's description:
> Reland CHECKs that verify bookmark USS invariants
> 
> Relands invariant-checking logic reverted in
> https://chromium-review.googlesource.com/c/1378135 after having fixed
> the issue with the root node, which may not be tracked if the sync
> data was supplied by the USS migrator.
> 
> TBR=jkrcal@chromium.org
> 
> Bug: 915198
> Change-Id: I2e3db80d14d8f4a07bc395e1fec46ff9af6a7b8c
> Reviewed-on: https://chromium-review.googlesource.com/c/1378857
> Reviewed-by: Mikel Astiz <mastiz@chromium.org>
> Commit-Queue: Mikel Astiz <mastiz@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#616994}

TBR=jkrcal@chromium.org,mastiz@chromium.org

Change-Id: I3744019474dfd5939703186e8d9d1481bf109333
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 915198
Reviewed-on: https://chromium-review.googlesource.com/c/1378982
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Commit-Queue: Mikel Astiz <mastiz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#617014}
1 file changed