Migrate sidebar item pref for built-in items which do not specify built-in-item-type

[petemill]

Avoid crash by not trying to load them, but also migrate these items to include the item type key, bringing back the function to find built-in item type from url.

This crash was occuring on Nightly for some users who had modified sidebar preferences close to the time that it was initially released and not modified the preferences since.

Resolves brave/brave-browser#24965
Additionally, from #14800:
Resolves https://github.com/brave/internal/issues/899
Resolves https://github.com/brave/internal/issues/900
Resolves https://github.com/brave/internal/issues/901

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
• Squashed any review feedback or "fixup" commits before merge, so that history is a record of what happened in the repo, not your PR
• 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:

On any profile, open the Preferences file in a code editor, and replace the "brave.sidebar" section with the following:

    "sidebar": {
      "sidebar_items": [
        {
          "open_in_panel": true,
          "title": "Brave Together",
          "type": 0,
          "url": "https://together.brave.com/"
        },
        {
          "open_in_panel": false,
          "title": "Crypto Wallets",
          "type": 0,
          "url": "chrome://wallet/"
        },
        {
          "open_in_panel": true,
          "title": "Bookmarks",
          "type": 0,
          "url": "chrome://bookmarks/"
        },
        {
          "open_in_panel": true,
          "title": "History",
          "type": 0,
          "url": "chrome://history/"
        },
        {
          "open_in_panel": false,
          "title": "Settings - About Brave",
          "type": 1,
          "url": "chrome://settings/help"
        }
      ]
    },

[petemill]

This is where the crash was, I would guess. It shouldn't get here anymore because of the fix earlier in the stack, but it's better to keep a check here.

[petemill]

I verified that this new test fails with the version of SidebarService previous to this PR, and passes with this PR.

[petemill]

These lines solve the issue since we should skip parsing the item if we have bad data. The previous version of this line was missing the continue. Plus it isn't immediately obvious that:

if (const auto value =
                item.FindIntKey(kSidebarItemBuiltInItemTypeKey)

is the same as:

        const auto value = item.FindIntKey(kSidebarItemBuiltInItemTypeKey);
        if (!value.has_value()) 

[simonhong]

++

[simonhong]

base::ranges::find_if

[petemill]

I have addressed all feedback and rebased on #14800 so that it is ready. We can even merge all together in this PR for most optimized CI and merge and easy uplift.

addressed and rebased

[cdesouza-chromium]

LGTM