Tor profile rework

[yrliou]

Fix brave/brave-browser#2307

It would be easier to review this PR per commit.
What this PR does:

• Tor profile is not based on guest profiles anymore, when SwitchToTorProfile is called, we will create a dummy regular Tor profile and use its off-the-record profile to browse.
• Service factories are hooked to inherit bookmarks(3418ed7), preferences(0979ed1) from its parent profile (the one that is used before switching to Tor profile). Our behavior should be the same with private window for these two.
• Navigation requests to pages like brave://settings will be redirected back to its parent profile.
  (601b6f1)
• unit and browser tests

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:

1. Open the browser and go to brave://settings and disable Show bookmarks bar.
2. Visit https://check.torproject.org and add the page into bookmarks.
3. Open a tor window, the new tab page bookmark bar should show the one we added in step 2.
4. Visit https://check.torproject.org in Tor window, it should show we're using Tor network.
5. Go back to the normal window and go to brave://settings and enable Show bookmarks bar
6. Go back to the https://check.torproject.org in Tor window, it should now display the bookmark bar with the bookmark we added in step 2.
7. Add a bookmark again in the normal window, it should show up in the Tor window too.
8. Delete a bookmark from the Tor window, it should disappear in the normal window too.
9. Delete a bookmark from the normal window, it should disappear in the Tor window too.
10. Open brave://settings in Tor window, it should open or go to the existing settings page in the normal window.

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.

[yrliou]

We cannot always use ProfileManager directly to get Tor parent profile by its path because we need to access this during shutdown when ProfileManager is already going away and g_browser_process->profile_manager() returns null in this case, so I end up putting it in Profile class (it is needed by both ProfileImpl and TestingProfile).

[yrliou]

For the TODO to fix SearchEngineProviderServiceTest.CheckDefaultTorProfileSearchProviderTest breakage, I'm thinking of disabling the search engine pref retention test part in SearchEngineProviderServiceTest.CheckDefaultTorProfileSearchProviderTest because we shouldn't retain the pref in Tor profile but should be in its parent profile.
We could introduce the setting UI later in the normal profile's settings page to address brave/brave-browser#2158.

[darkdh]

overall looks good

[yrliou]

This test was expecting the search engine pref in Tor profile to be retained across the sessions which is not true after this PR. Since we don't have UI exposed to users at the moment (Settings page in Tor profile is an empty page for release builds at the moment.) and we have an open issue to change the search engine in the normal profile (the parent profile) brave/brave-browser#2158, I think it's better to readdress the functionality of changing search engines for Tor profile while fixing brave/brave-browser#2158.

[yrliou]

Only CI failure is a known intermittent error in linux network-audit, but it was passing in previous tries, should be safe to ignore this one.

17:00:00  undefined:18078
17:00:00  {"phase":2,"source":{"id":84,"type":8}]}
17:00:00                                        ^
17:00:00  
17:00:00  SyntaxError: Unexpected token ] in JSON at position 78216892
17:00:00      at JSON.parse (<anonymous>)
17:00:00      at start (/home/ubuntu/jenkins/workspace/_tor_profile_rework_take2_rebase/lib/start.js:144:23)
17:00:00      at Command.listener (/home/ubuntu/jenkins/workspace/_tor_profile_rework_take2_rebase/node_modules/commander/index.js:315:8)
17:00:00      at Command.emit (events.js:203:13)
17:00:00      at Command.parseArgs (/home/ubuntu/jenkins/workspace/_tor_profile_rework_take2_rebase/node_modules/commander/index.js:654:12)
17:00:00      at Command.parse (/home/ubuntu/jenkins/workspace/_tor_profile_rework_take2_rebase/node_modules/commander/index.js:474:21)
17:00:00      at Object.<anonymous> (/home/ubuntu/jenkins/workspace/_tor_profile_rework_take2_rebase/scripts/commands.js:155:4)
17:00:00      at Module._compile (internal/modules/cjs/loader.js:868:30)
17:00:00      at Object.Module._extensions..js (internal/modules/cjs/loader.js:879:10)
17:00:00      at Module.load (internal/modules/cjs/loader.js:731:32)
17:00:00  npm ERR! code ELIFECYCLE
17:00:00  npm ERR! errno 1
17:00:00  npm ERR! brave@0.72.66 network-audit: `node ./scripts/commands.js start --enable_brave_update --network_log --user_data_dir_name=brave-network-test "--output_path=src/out/Release/brave"`
17:00:00  npm ERR! Exit status 1
17:00:00  npm ERR! 
17:00:00  npm ERR! Failed at the brave@0.72.66 network-audit script.
17:00:00  npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
17:00:00  
17:00:00  npm ERR! A complete log of this run can be found in:
17:00:00  npm ERR!     /home/ubuntu/.npm/_logs/2019-10-02T23_59_49_713Z-debug.log

[rvklein]

Was forwarded here from this issue thread:
brave/brave-browser#2761

Please consider adding the ability to use browser extensions when running in Tor mode. This is incredibly important for a11y features such as user stylesheets, machine translation, colour inversion, forced high contrast, screen readers, and more.