Implement ability to remove other devices in chain for sync v2

[AlexeyBarabash]

Need to implement ability to remove other devices from the sync chain for sync v2

We have feedback that such ability is very required: https://community.brave.com/t/how-to-remove-device-not-available-from-sync-list/152615 .

Please use test plan at the PR brave/brave-core#6732

[AlexeyBarabash]

Related comment brave/brave-core#5361 (review)

[w0ts0n]

+1 here
https://reddit.com/r/brave_browser/comments/i9jip8/each_device_can_be_managed_from_any_other_device/

[srirambv]

Verification passed on OnePlus 6T with Android 10 running 1.18.63 x64 beta build

• Verified trash button is shown on all listed devices in sync chain
  
• Verified able to remove other devices by tapping on the trash bin button next to the device name
  

---

Verification passed on Samsung Tab A with Android 10 running 1.18.63 x64 beta build

• Verified trash button is shown on all listed devices in sync chain
  

• Verified able to remove other devices by tapping on the trash bin button next to the device name
  

[bharatmk256]

Trash icon is not visible for every devices
Brave beta 1.18.63
Android 10

[GeetaSarvadnya]

Verification passed on

Brave | 1.18.68 Chromium: 87.0.4280.67 (Official Build) dev (64-bit)
-- | --
Revision | 0e5d92df40086cf0050c00f87b11da1b14580930-refs/branch-heads/4280@{#1441}
OS | Windows 10 OS Version 2004 (Build 19041.630)

Note: on Desktop and on Android the trash icon is shown only if the remote device in chain supports self-delete, version must be above 1.18.19

• Verified the test plan from Sync remove other device brave-core#6732

Clean profile

• Verified that Trash icon isn't shown for the desktop device C (this device) as the desktop has Leave Sync Chain option.
  Device A - Android 1.18.67
  Device B - Desktop 1.17.x
  Device C - Desktop 1.18.68
  

• Verified that on each device in the devices list displayed with the trashcan icon
  Device A - Desktop 1.18.68
  Device B - Android 1.18.67
  Device C - Desktop 1.19.43

Device A in a sync chain

Device B in a sync chain

Device C in a sync chain

• Ensured that devices B and C are no longer exists in device A after removing devices B and C by tapping on the Trash icon in device A
• Ensured that sync chain reset happened automatically on device B and C after removing them from device A
• Rejoin Device B and C to sync chain with device A and ensured that all the three devices are in sync chain
• In Android device C removed the Device B and ensured that device B is no longer exists in device A and device C and Device B automatically self reset the sych chain.

Upgraded profile

Device A: 1.17.x dev version
Device B: 1.19.x

• Setup sync chain between device A and B and ensured that the trash icon isn't shown in both devices A and B
• Upgrade the profile to 1.18.68 in device A, verified that the Trash icon is shown in each remote device in sync chain after upgrade to 1.18.x

[GeetaSarvadnya]

@bharatmk256 If you have installed the brave version which is below the self delete version 1.18.19 then the trash icon will not be shown, which is expected. Please install brave version which is higher than 1.18.19 in all the devices in a sync chain, you should be able to see the trash icon in all the devices in the sync chain, if you are not seeing the trash icon then it's a bug.

[cardin]

Is there any plans to support unsyncing devices that are not higher than 1.18.19?

[AlexeyBarabash]

@cardin
Sorry, we are unable to make it because this is impossible.

The client must do some actions to be removed from the chain in a proper way.

Inherited part code from Chromium does cleanup for devices which hadn't do any activity for a long period (~3 months if I remember correctly).

[WueXiang]

@AlexeyBarabash although I dont know what is the mechanism behind this sync chain, I am pretty sure in a way or two something can be done to solve this issue. Something like letting user to clone contents from old sync chain and put it into a new sync chain, then migrate their devices to new sync chain one by one?

[AlexeyBarabash]

Hello @WueXiang,

Thanks, this is good idea. We will be able to do something similar to what you have suggested when we will split the chain id from the encryption key.
Right now the advise is to re-create sync chain and re-add only the devices which are required.