Match exact host in autoplay whitelist before matching eTLD+1

[pilgrim-brave]

Resolves brave/brave-browser#4621

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:

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.

[bbondy]

looks right to me, but will wait for confirmation that it works. A couple of unit tests would be super too.

[pilgrim-brave]

simplified the test data file and added multiple tests

[pilgrim-brave]

AFAICT this only failed because of Github's connectivity issues yesterday, but I'll rebase it and run it through again just to be sure.

[bsclifton]

Added missing milestone to this PR and brave/brave-browser#4621

[pilgrim-brave]

uplifted to release

[kjozwiak]

Reproduced the original issue on macOS 10.15.3 x64 using the following builds:

Brave | 1.7.21 Chromium: 80.0.3987.122 (Official Build) nightly (64-bit)
--- | ---
Revision | cf72c4c4f7db75bc3da689cd76513962d31c7b52-refs/branch-heads/3987@{#943}
OS | macOS Version 10.15.3 (Build 19D76)

Brave | 1.4.95 Chromium: 80.0.3987.122 (Official Build) (64-bit)
-- | --
Revision | cf72c4c4f7db75bc3da689cd76513962d31c7b52-refs/branch-heads/3987@{#943}
OS | macOS Version 10.15.3 (Build 19D76)

• Using the STR mentioned via No audio output in Google Meet (blocked by autoplay) brave-browser#4621 (comment), reproduced the issue of the audio not working once pressing on Test under Speaker.

Verification PASSED on macOS 10.15.3 x64 using the following build:

Brave | 1.7.35 Chromium: 80.0.3987.122 (Official Build) nightly (64-bit)
-- | --
Revision | cf72c4c4f7db75bc3da689cd76513962d31c7b52-refs/branch-heads/3987@{#943}
OS | macOS Version 10.15.3 (Build 19D76)

• Went through the STR outlined via No audio output in Google Meet (blocked by autoplay) brave-browser#4621 (comment) and ensured that sound was being played when selecting Test under Speaker.
• Had a quick call with @rebron and ensured that the sound was being played without the need to allow autoplay permissions under https://meet.google.com.

[kjozwiak]

Moving this out of https://github.com/brave/brave-core/milestone/56 as this specific PR is on master. #4788 is the PR that belongs in https://github.com/brave/brave-core/milestone/56.