Remove sync v1 leftovers

[AlexeyBarabash]

Resolves brave/brave-browser#15791

This PR removes some sync v1 extension leftovers.

Submitter Checklist:

• I confirm that no security/privacy review is needed, or that I have requested one
• There is a ticket for my issue
• Used Github auto-closing keywords in the PR description above
• Wrote a good PR/commit description
• Added appropriate labels (QA/Yes or QA/No; release-notes/include or release-notes/exclude; OS/...) to the associated issue
• Checked the PR locally: npm run test -- brave_browser_tests, npm run test -- brave_unit_tests, npm run lint, npm run gn_check, npm run tslint
• Ran git rebase master (if needed)

Reviewer Checklist:

• A security review is not needed, or a link to one is included in the PR description
• New files have MPL-2.0 license header
• Adequate test coverage exists to prevent regressions
• Major classes, functions and non-trivial code blocks are well-commented
• Changes in component dependencies are properly reflected in gn
• Code follows the style guide
• Test plan is specified in PR before merging

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on
• All relevant documentation has been updated, for instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Custom-Headers
  • https://github.com/brave/brave-browser/wiki/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

N/A

[samartnik]

lgtm

[AlexeyBarabash]

macOSX build is marked is UNSTABLE,

Failed
macos-x64 / test-browser / AdBlockServiceTest.CnameCloakedRequestsGetBlocked

• not related to the PR

[AlexeyBarabash]

Pre-init CI step is UNSTABLE
https://ci.brave.com/job/pr-brave-browser-sync_v1_leftovers-pre-init/2/execution/node/139/

Node Record compiler warnings and static analysis results
Parents
Shell Script

{unstableTotalAll=1, sourceCodeEncoding=UTF-8, tools=[@pyLint(pattern=pylint-report.txt,reportEncoding=UTF-8)], failOnError=true}

at the same time npm run pylint -- --compare-with master gives the same errors both on master and on sync_v1_leftovers :

 [email protected] pylint /mnt/EVO970/Projects/br_br_master/brave-browser/src/brave
 ./script/pylint.sh "--compare-with" "master"

Checking for pylint findings in scripts changed relative to master in: build/ components/ installer/ script/ tools/
Module audit_deps
C: 68, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C: 75, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C: 91, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C:101, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C:105, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C:110, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C:111, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
C:114, 0: Unnecessary parens after 'print' keyword (superfluous-parens)
W:105,52: Used builtin function 'map'. Using a list comprehension can be clearer. (bad-builtin)

so not related to the PR