Sync chain not being reset when Main device is removed

[LaurenWags]

Description

Found while testing brave/brave-core#1019

If you have a sync chain with two devices, when you remove the main device (Device A), the sync chain is not being reset on second device.

Device A - macOS Laptop
Device B - Linux VM

Steps to Reproduce

1. Setup sync between Device A and B
2. On Device A, remove itself
3. Sync is reset on Device A
4. Go over to Device B

Actual result:

Sync is not reset on Device B

https://drive.google.com/file/d/1Qmuu0UqatUjKVcfVrYidtfp1lx5OTtOX/view?usp=sharing

Expected result:

Sync to be reset on both devices since you need two devices for a sync chain.

Reproduces how often:

easily

Brave version (brave://version info)

Brave	0.58.12 Chromium: 71.0.3578.80 (Official Build) (64-bit)
Revision	2ac50e7249fbd55e6f517a28131605c9fb9fe897-refs/branch-heads/3578@{#860}
OS	Mac OS X

and 0.58.12 on Linux VM as well.

Reproducible on current release:

• Does it reproduce on brave-browser dev/beta builds? yes

Website problems only:

• Does the issue resolve itself when disabling Brave Shields? n/a
• Is the issue reproducible on the latest version of Chrome? n/a

Additional Information

cc @brave/legacy_qa for verification on other platforms

[kjozwiak]

Waiting on new build as the PR landed ~11hrs ago. Still reproducible under 0.58.14 Chromium: 71.0.3578.98 which was built ~3 days ago on Friday.

[GeetaSarvadnya]

Verification passed on

Brave	0.59.12 Chromium: 72.0.3626.17 (Official Build) beta (64-bit)
Revision	08d2140079f8db14c9eb885a803d231b1a30e817-refs/branch-heads/3626@{#315}
OS	Windows 10

• Verified the STR mentioned in the issue.

Verification passed on

Brave 0.59.12 Chromium: 72.0.3626.17 (Official Build) beta (64-bit)
Revision 08d2140079f8db14c9eb885a803d231b1a30e817-refs/branch-heads/3626@{#315}
OS Linux

• Verified the STR mentioned in the issue.

Verified passed with

Brave	0.59.14 Chromium: 72.0.3626.28 (Official Build) beta(64-bit)
Revision	997b1040b63bac324e815797ba52be0cd8f616ed-refs/branch-heads/3626@{#461}
OS	Mac OS X

• Verified STR from description
• Verified test plan in Fix UI initialization flow and reset when devices < 2 from native side brave-core#1109