Show sync setup error

[AlexeyBarabash]

Address brave/brave-browser#2103 .

This is PR for brave/brave-browser#2103 and for Expected results pt2 for brave/brave-browser#2130 .
Contains required native-code changes, but does not close the issue entirely.
Issue still require to proper implement of

function syncSetupError(error: string) {
    alert('Sync setup error: ' + error)
  }

in components/brave_sync/ui/brave_sync.tsx

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).
• Verified that these changes build without errors on
  • Windows
  • macOS
  • Linux
• Verified that these changes pass automated tests (npm test brave_unit_tests && npm test brave_browser_tests) on
  • Windows
  • macOS
  • Linux
• Ran git rebase master (if needed).
• 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.
• Add appropriate QA labels (QA/Yes or QA/No) to include the closed issue in milestone

Test Plan:

1. Take code words and make the last word to be wrong
2. Connect to existing sync chain with words from pt1
3. Should appear the message wrong code words

Reviewer Checklist:

• New files have MPL-2.0 license header.
• Request a security/privacy review as needed.
• Adequate test coverage exists to prevent regressions
• Verify test plan is specified in PR before merging to source

[AlexeyBarabash]

I see 3 failed browser tests

2 tests failed:
    NavigatorPluginsTest.ConstMimeTypesWithFlash (../../brave/chromium_src/third_party/blink/renderer/modules/plugins/navigator_pluginstest.cc:112)
    NavigatorPluginsTest.ConstPluginsWithFlash (../../brave/chromium_src/third_party/blink/renderer/modules/plugins/navigator_pluginstest.cc:96)
1 test timed out:
    BraveExtensionProviderTest.PDFJSInstalls (../../brave/browser/extensions/brave_extension_provider_browsertest.cc:40)

[AlexeyBarabash]

There is a separate issue for ui design for the error message: brave/brave-browser#2128. So this PR address brave/brave-browser#2103 .

[darkdh]

lgtm, could you squash 1397cb1cf6a7f126edb1ab3479bf7f9b14034ef3 (1) and 01983484e2e0044ee20da721515628763b288f53 (4) into b94973a6cd4c4cdb1a7c8ffa23b898c3f5c597e7 (2)? And I will approve

[cezaraugusto]

@AlexeyBarabash please change the word in the PR comment to address instead of fixes as it need work on my end to close it. otherwise github will use the auto-close keyword. I'm coming up with a follow-up w/ the missing part

[AlexeyBarabash]

@darkdh , squashed commits, also rebased the branch to today's master.

[AlexeyBarabash]

master 828f316
0.57.x 71d1fd3
0.58.x f3a9146