Adds contribution queue

[NejcZdovc]

Resolves brave/brave-browser#6288

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
  • Android
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that these changes pass automated tests (unit, browser, security tests) on
  • iOS
  • Linux
  • macOS
  • Windows
• 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).
• 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
• 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
  • https://github.com/brave/brave-browser/wiki/QA-Guide

Test Plan:

• enable rewards with short contribution interval
• claim grant (30 BAT)
• set AC amount to 20 BAT
• add verified publishers to AC table
• add verified recurring tips in this order (5, 10, 10, 10)
• wait for monthly contribution to trigger
• you should see 25 BAT goes through for monthly and 5 BAT from AC

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.

[NejcZdovc]

marked it so that CI can do first pass

[NejcZdovc]

@tmancey @kylehickinson not ready for a review yet

[NejcZdovc]

have it in for now as test is failing on CI, will remove at the end

[tmancey]

LGTM++

[NejcZdovc]

CI is failing with this issue brave/brave-browser#6515. Everything else passed

[LaurenWags]

Verified with

Brave	0.73.8 Chromium: 78.0.3904.50 (Official Build) nightly (64-bit)
Revision	2accdc52c79976e264cd2694df6db31d1fccd8e8-refs/branch-heads/3904@{#658}
OS	macOS Version 10.13.6 (Build 17G5019)

• Verified test plan from PR 3x, no issues. Tip that could not be completed was not put in the 'Pending' list as expected.

• Ran the following scenario. Verified the 3rd tip of 10 BAT was skipped but the tip for 1 BAT after it was completed. So a total of 26 BAT for recurring tips was contributed and 4 BAT to verified publishers only was contributed as expected.

1. enable rewards with short contribution interval on staging
2. claim grant (30 BAT)
3. set AC amount to 20 BAT
4. add verified and non verified publishers to AC table
5. add verified recurring tips in this order (5, 10, 10, 10, 1)
6. wait for monthly contribution to trigger
7. you should see 26 BAT goes through for monthly and 4 BAT from AC

• Ran the following scenario. Received unexpected/incorrect messages at noted places. Logged receiving Insufficient Funds/AC can't be completed messages incorrectly - follow up to 6288 brave-browser#6546 for this. Other than the incorrect messages, scenario completed as expected.

1. enable rewards with short contribution interval on staging
2. claim grant (30 BAT)
3. set AC amount to 20 BAT
4. add verified and unverified publishers to AC table
5. add verified recurring tips in this order (5, 10, 10, 10)
6. Restart browser
   ---> See notification about Insufficient Funds. Dismiss it.
7. wait for monthly contribution to trigger
8. you should see 25 BAT goes through for monthly and 5 BAT from AC
   ---> Get notice that AC couldn't be completed, will try again in 30 days message. Note - both AC and recurring tips appear to have been contributed.

• Also logged Left sig != right sig. Signature check failure. message occurs very frequently - follow up to 6288 brave-browser#6545 as I experienced a lot of Left sig != right sig. Signature check failure. messages in the logs while testing this. As a result, some of my ballots didn't go out so my publishers didn't receive all of the expected BAT. This is something that occurs today, but to my knowledge it is infrequent. While testing it happened pretty much each time I executed scenarios for this PR and should be addressed.

[NejcZdovc]

yup saw 6545 for some time now, already asked for any hints from other teams as my current theory is that it's related to chromium bump. 6545 is not related to this PR

[LaurenWags]

Not a conclusive test, but I did just run two auto contribute only tests (no monthly recurring tips) with the same build (0.73.8) and did not see the Left sig != right sig. Signature check failure. message at all. All expected BAT was transferred to the test publisher account I used.

Maybe it's related to recurring tips?

[NejcZdovc]

@LaurenWags not sure, it's for now random for me, don't have STR yet