[Desktop] Devices are not synced after upgrade from V1

[GeetaSarvadnya]

Description

Devices are not synced after upgrade from V1. Network error is shown in the brave://sync-internals even though there is no network issue. The issue is not reproducible in 1.14.34 ( upgrade from 1.11.x to 1.14.34). The issue persists when upgrading 1.11.x to 1.12.x

Device Details

Device A: windows 10 (physical machine)
Device B: windows 10 (VM)

Steps to Reproduce

1. Install 1.11.104 on both devices A, B
2. Launch brave with a clean profile and enable sync in both devices via chrome://flags
3. Establish sync between Devices A, B
4. Bookmark cnn.com in Device A and make sure it gets synced in Device B
5. Upgrade profiles to 1.12.112 in both Devices A, B
6. Ensure sync chain is not retained but the bookmark is retained in both devices
7. Open brave://sync in Device A and Device B
8. Start a sync chain in Device A and copy the code from Device A and paste it in Device B and click confirm in both devices
9. Devices are not synced at all ( waited for 10 to 15 mins)

Actual result:

Devices are not synced after upgrade from V1

brave://sync-internals

Expected result:

Devices should be synced after upgrade from V1

Reproduces how often:

Always

Brave version (brave://version info)

Brave	1.12.112 Chromium: 84.0.4147.125 (Official Build) (64-bit)
Revision	d0784639447f2e10d32ebaf9861092b20cfde286-refs/branch-heads/4147@{#1059}
OS	Windows 10 OS Version 1903 (Build 18362.959)

Version/Channel Information:

• Can you reproduce this issue with the current release? NA
• Can you reproduce this issue with the beta channel? Not sure
• Can you reproduce this issue with the nightly channel? No - 1.14.34

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? NA
• Does the issue resolve itself when disabling Brave Rewards? NA
• Is the issue reproducible on the latest version of Chrome? NA

Miscellaneous Information:

cc: @brave/legacy_qa @jsecretan @rebron @darkdh

[darkdh]

according to the screenshot you shared on slack

--sync-url=https://no-thanks.invalid that is the reason
which might related to #8263 because some of the old features retained and duplicated
However, relaunch will make the --sync-url right.

[GeetaSarvadnya]

@darkdh After the relaunch issue is fixed. Devices are synced in V2

[GeetaSarvadnya]

This issue persists in android also. Verified on BraveModernarm 1.12.112 on Android version 5.1.1. Unable to sync devices after upgrade from v1, but when I restart the browser in Android, devices are getting synced in V2.

[GeetaSarvadnya]

@srirambv If this issue is taken care in other issues in Android repo, please remove the OS/Android label and link the issue id here.

[jsecretan]

Given the launch of Sync v2, I think this is probably no longer relevant as many who would upgrade have already done so.