Revert "Introduce an error badge shows on top of the ntp avatar"

This reverts commit c09242ff37a0cc11c89596226bf0ea21a163514b.

Reason for revert:
CL broke org.chromium.chrome.browser.sync.settings.ManageSyncSettingsTest#testSyncHistoryAndTabsToggle_typeManagedByCustodian_historyOptInEntryPointsEnabled
BUG=394583571

Original change's description:
> Introduce an error badge shows on top of the ntp avatar
>
> The error badge shows in case of an identity error. This change lives
> behind the UNO_PHASE_2_FOLLOW_UP feature flag, which is currently
> disabled by default.
>
> This CL also fixes badge position calculations in
> ProfileDataCache.overlayBadgeOnUserPicture() to use float for some
> calculations. This improves the accuracy of the badge's center position
> by avoiding integer division.
>
> Bug: 376658293
> Change-Id: I8c7eba58688250bf8e68b58ea76a4ea3ae0d392c
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6219310
> Commit-Queue: Mahmoud Rashad <mmrashad@google.com>
> Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1415639}

Bug: 376658293
Change-Id: Ief81e9d6872d6ee2008e123aaed9f8f28c9db11b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6234518
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Peter Kotwicz <pkotwicz@chromium.org>
Auto-Submit: Peter Kotwicz <pkotwicz@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1416212}