[Brave News] Don't use the |is_enabled| flag when determining if the publisher is subscribed.

[fallaciousreasoning]

Resolves brave/brave-browser#26324

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

[petemill]

Looks like you just need to run npm run format to fix the lint issue in CI

[stephendonner]

@petemill @fallaciousreasoning what's the test plan for this? My original steps don't readily apply, since we're now enabled with Brave News V2.

[petemill]

@stephendonner I'm actually quite confused by the test steps in brave/brave-browser#26324. At no point to they instruct to follow The Atlantic, so I'm not sure how disabling the v2 flag will help. If it's useful, it can be disabled at launch with --disable-features=BraveNewsV2

[fallaciousreasoning]

Right, yeah:

1. On a new profile (with the subscribe button enabled, and Brave News opted in)
2. Following only the top sources channel
3. Navigate the theatlantic.com
4. The atlantic should NOT show as followed in the Brave News button

(previously it was showing up as followed).

[stephendonner]

Verified PASSED using

Brave	1.47.91 Chromium: 108.0.5359.48 (Official Build) nightly (x86_64)
Revision	18ceeca0d99318e70c00d2e04d88aa55488b5c63-refs/branch-heads/5359@{#854}
OS	macOS Version 11.7.1 (Build 20G918)

Steps:

1. install 1.47.91
2. launch Brave
3. open brave://flags
4. set brave://flags/#brave-news-subscribe-button to Enabled
5. clicked Relaunch
6. opened a new-tab page
7. clicked on Customize
8. clicked on Brave News
9. clicked on Turn on Brave News
10. confirmed I was default following Top Sources, in the Following column
11. loaded theatlantic.com
12. clicked on the Manage Subscriptions button
13. examined the The Atlantic and Best of the Atlantic feeds' statuses

Confirmed neither The Atlantic nor Best of the Atlantic were Followed/shown as Followed

example	example (issue brave/brave-browser#26262)	example	example