disable account consistency

[bridiver]

fix brave/brave-browser#338

requires #172 for test

I tried setting prefs and several other methods to avoid patching, but this was the only thing that worked reliably

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.
• Request a security/privacy review as needed.

Test Plan:

Reviewer Checklist:

• New files have MPL-2.0 license header.
• Request a security/privacy review as needed.
• Adequate test coverage exists to prevent regressions

[bridiver]

see https://bugs.chromium.org/p/chromium/issues/detail?id=831824 for upstream issue

[bridiver]

check upstream fix https://chromium.googlesource.com/chromium/src.git/+/4fd11d48d6c82826fe8c84aaaf81d9449d81c23e when available and remove