Do not show 0% after normalization

[NejcZdovc]

Resolves brave/brave-browser#4386

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
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• Verified that these changes pass automated tests (npm test brave_unit_tests && npm test brave_browser_tests && npm run test-security) on
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• Verified that all lint errors/warnings are resolved (npm run lint)
• Ran git rebase master (if needed).
• Ran git rebase -i to squash commits (if needed).
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• Request a security/privacy review as needed.
• Add appropriate QA labels (QA/Yes or QA/No) to include the closed issue in milestone
• Public documentation has been updated as necessary. 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-Protection-Mode
  • 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-issues-with-tracking-protection

Test Plan:

• enable rewards
• add couple of sites so that some publishers will have % 0
• open rewards page
• click on all sites
• make sure that you don't see 0 % publishers
• open new window
• start watching youtube video
• make sure that after 2min of the video you still don't see 0 % publishers in all sites modal

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

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.

[tmancey]

LGTM++

[tmancey]

LGTM++ (security tests are failing which look unrelated but please check before merging)

[bridiver]

I don't think this is the right place to do this. This is UI logic and should be filtered by the UI, not by RewardsServiceImpl

[bridiver]

also there should be a test for this

[NejcZdovc]

this was added here as other (sort is here as well) that is then sent to UI. Left comment here how I want to solve it https://github.com/brave/brave-core/pull/2432/files#r283678712

[bridiver]

The sort is also here which is UI, but I think even short-term it would be better to move both of those to the UI class OnPublisherListNormalized observer method. I think we're all on the same page now that we should be doing the calculations at query time and dumping the serialized normalization? If not let's discuss in slack with @tmancey as well