Fix vpn's invalid selected name crash

[simonhong]

Resolves

fix brave/brave-browser#41093

Submitter Checklist:

• I confirm that no security/privacy review is needed and no other type of reviews are needed, or that I have requested them
• 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 wiki
  • npm run presubmit wiki, 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/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

See the linked issue for manual test

[deeppandya]

Migration LGTM. how would it behave for an upgrade scenario ?

[simonhong]

Migration LGTM. how would it behave for an upgrade scenario ?

When upgraded, new region list data & timezone data are fetched again as previously cached region list became invalid.
Then, it sets device region again with timezone data with new name as timezone uses old name still.
(Maybe we need to use new guardian timezone fetch api later?)
With new device region, it's set to selected region again if it's empty.
If user already has selected region, it is migrated to new name during the startup and it's not changed again with device region.

[deeppandya]

Migration LGTM. how would it behave for an upgrade scenario ?

When upgraded, new region list data & timezone data are fetched again as previously cached region list became invalid. Then, it sets device region again with timezone data with new name as timezone uses old name still. (Maybe we need to use new guardian timezone fetch api later?) With new device region, it's set to selected region again if it's empty. If user already has selected region, it is migrated to new name during the startup and it's not changed again with device region.

I am definitely going to reach out to guardian team for new timezone api.

[deeppandya]

LGTM

[MadhaviSeelam]

Verification PASSED using

Brave | 1.72.26 Chromium: 129.0.6668.59 (Official Build) nightly (64-bit)
-- | --
Revision | 4580158f4966388aa15f701b5fa01cbe22846cc5
OS | Windows 11 Version 23H2 (Build 22631.4169)

1. Installed 1.72.26
2. launched Brave
3. logged into account.bravesoftware.com as an existing VPN subscriber (refresh39132vpn627@mailinator.com)
4. clicked Refresh Firewall + VPN button on the subscription page
5. waited for few seconds
6. clicked VPN button in the toolbar
7. enabled/disabled via VPN panel, hamburger menu and taskbar VPN icon
8. switched to different region - Sweden
9. opened whatismyipaddress.com

• Confirmed no crash happened
• VPN worked as expected
• confirmed correct region is shown

2024-09-20_09h05_07.mp4