QR code/words don't display if you try to join a sync chain before starting a new one

[LaurenWags]

Description

Similar to #2533, #2537

If you open 'Enter a sync chain code' and then go to 'Start a new sync chain', the QR code and words won't display.

Steps to Reproduce

1. Clean profile 0.58.12
2. Navigate to brave://sync
3. Click on Enter a sync chain code.
4. Click Cancel or X
5. Click on Start a new sync chain
6. Choose Phone/Tablet or Computer

Actual result:

No QR code or words are displayed:

Expected result:

QR code/words should be displayed. Refresh of page resolves this issue.

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

Reproducible on current release:

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

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

[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

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