Closing private window without Tor sometimes kills tor daemon

[riastradh-brave]

Description

If a private window without Tor, from which a private window with Tor was opened, is closed, Brave kills the tor daemon.

Steps to Reproduce

1. Launch Brave.
2. Open a private window (without Tor).
3. From that private window, open a private window with Tor.
4. Close the original private Window (the one without Tor).

Actual result:

Brave kills the tor daemon (by sending it SIGTERM, on Unix).

Expected result:

The tor daemon should continue running uninterrupted.

Reproduces how often:

100%

Brave version (brave://version info)

Everything from current release to the bleeding edge I built a few minutes ago -- not sure when it started:

Brave	1.6.3 Chromium: 80.0.3987.85 (Official Build) unknown (64-bit)
Revision	583b05dfa4ffc657f0f7c5cc13f53aa17c9a5bcf-refs/branch-heads/3987@{#791}
OS	Linux
JavaScript	V8 8.0.426.16
Flash	(Disabled)
User Agent	Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.85 Safari/537.36
Command Line	./src/out/Release/brave --user-data-dir=/tmp/riastradh/test20200205 --enable-dom-distiller --disable-domain-reliability --no-pings --extension-content-verification=enforce_strict --extensions-install-verification=enforce --sync-url=https://no-thanks.invalid --enable-features=PasswordImport,WebUIDarkMode,SimplifyHttpsIndicator --disable-features=AllowPopupsDuringPageUnload,AudioServiceOutOfProcess,SmsReceiver,NotificationTriggers,LookalikeUrlNavigationSuggestionsUI,AutofillServerCommunication,WebXR,VideoPlaybackQuality,WebXrGamepadModule --flag-switches-begin --flag-switches-end --disable-webrtc-apm-in-audio-service
Executable Path	/home/riastradh/brave/brave/src/out/Release/brave
Profile Path	/tmp/user/1000/test20200205/Default

Version/Channel Information:

• Can you reproduce this issue with the current release?
  • yes
• Can you reproduce this issue with the beta channel?
  • yes
• Can you reproduce this issue with the dev channel?
  • yes
• Can you reproduce this issue with the nightly channel?
  • yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
  • no
• Does the issue resolve itself when disabling Brave Rewards?
  • no
• Is the issue reproducible on the latest version of Chrome?
  • N/A

Miscellaneous Information:

Originally reported here: https://old.reddit.com/r/brave_browser/comments/ey2tg7/can_somebody_reproduce_this_problem/

[riastradh-brave]

duplicate of #8076