3rd device doesn't show This Device entry in the sync chain

[GeetaSarvadnya]

Description

Found while testing #5770
When three devices are in sync, the 3rd device doesn't show This device entry in the sync chain.

Device

Device A: Beta (0.69.121)
Device B: Dev (0.70.80)
Device C: Nightly (0.71.57)

Steps to Reproduce

1. Create a sync chain in Device A
2. Add Device B to sync chain through Sync code
3. Add Device C to sync chain through Sync code
4. All the 3 devices listed in the sync chain for both Device A and Device B, But This Device entry isn't listed in Device C

Actual result:

3rd device doesn't show This Device entry in the sync chain

Expected result:

All the 3 devices should be displayed in the sync chain for all the three devices

Reproduces how often:

Always

Brave version (brave://version info)

Brave	0.71.57 Chromium: 76.0.3809.132 (Official Build) nightly (64-bit)
Revision	fd1acc410994a7a68ac25bc77513d443f3130860-refs/branch-heads/3809@{#1035}
OS	Windows 10 OS Version 1803 (Build 17134.523)

Version/Channel Information:

• Can you reproduce this issue with the current release? No
• Can you reproduce this issue with the beta channel? No
• Can you reproduce this issue with the dev channel? No
• Can you reproduce this issue with the nightly channel? Yes

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:

@brave/legacy_qa @AlexeyBarabash @darkdh

[btlechowski]

edit: Reproduced the issue on the latest nightly.

Beta: 0.69.121
Dev: 0.70.80
Nightly: 0.71.63

Steps:

1. Create sync on Beta
2. Sync Nightly
3. Wait 5 seconds
4. Sync Dev

Result:
Nightly build only gets 2 devices listed.

[GeetaSarvadnya]

Verification passed on

Brave	0.71.70 Chromium: 76.0.3809.132 (Official Build) dev (64-bit)
Revision	fd1acc410994a7a68ac25bc77513d443f3130860-refs/branch-heads/3809@{#1035}
OS	Windows 10 OS Version 1803 (Build 17134.523)

Brave	0.72.6 Chromium: 77.0.3865.65 (Official Build) nightly (64-bit)
Revision	87a331a3169cab563505fb44011058b904011ba1-refs/branch-heads/3865@{#726}
OS	Windows 10 OS Version 1803 (Build 17134.523)

Brave	0.69.124 Chromium: 76.0.3809.132 (Official Build) (64-bit)
Revision	fd1acc410994a7a68ac25bc77513d443f3130860-refs/branch-heads/3809@{#1035}
OS	Windows 10 OS Version 1803 (Build 17134.523)

• Verified the STR from the description
• Verified the sync between all the 4 channels (R-B-D-N), devices listed in each device as expected
• Verified the BM's synced in all the 4 devices
  Sync between Release-Dev-Nightly
  

Sync between Release-Beta-Dev-Nightly

Verification passed on

Brave	0.69.125 Chromium: 76.0.3809.132 (Official Build) (64-bit)
Revision	fd1acc410994a7a68ac25bc77513d443f3130860-refs/branch-heads/3809@{#1035}
OS	Ubuntu 18.04 LTS

• Verified the STR from the description
• Verified the STR from 3rd device doesn't show This Device entry in the sync chain #5866 (comment)
• Verified the sync between all the 4 channels
• Made sure that bookmarks are synced

Verified passed with

Brave	0.69.130 Chromium: 77.0.3865.90 (Official Build) (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	macOS Version 10.13.6 (Build 17G5019)

Brave	0.70.103 Chromium: 77.0.3865.90 (Official Build) beta (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	macOS Version 10.13.6 (Build 17G5019)

Brave	0.71.82 Chromium: 77.0.3865.90 (Official Build) dev (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	macOS Version 10.13.6 (Build 17G5019)

Brave	0.72.60 Chromium: 77.0.3865.90 (Official Build) nightly (64-bit)
Revision	58c425ba843df2918d9d4b409331972646c393dd-refs/branch-heads/3865@{#830}
OS	macOS Version 10.13.6 (Build 17G5019)

• Verified the STR from the description
• Verified the sync between all the 4 channels (R-B-D-N), devices listed in each device as expected
• Verified the BM's synced in all the 4 devices
  Top Row (L -> R): Release, Beta
  Bottom Row (L -> R): Dev, Nightly