favicons not loading correctly when enabling rewards via the panel

[kjozwiak]

Description

When enabling rewards via the BAT panel located in the URL while on a website, the wrong favicon source will be used. Example:

Using:

Instead of:

Which will result in the following:

Steps to Reproduce

1. launch 0.55.20 Chromium: 70.0.3538.67 using a brand new profile
2. visit wsj.com and enable rewards via the BAT icon in the URL
3. once enabled and the wallet is created, open a new tab and load ft.com
4. click on the BAT icon in the URL while on ft.com (you'll see the favicon)
5. switch back to the wsj.com tab and click on the BAT icon in the URL (favicon missing)

Now if you visit brave://rewards and refresh the wsj.com tab, the favicon will appear.

Actual result:

Expected result:

Favicons should be loading within the Rewards panel via the URL without any issues

Reproduces how often:

100% reproducible using the above STR

Brave version (brave://version info)

Brave	0.55.20 Chromium: 70.0.3538.67 (Official Build) (64-bit)
Revision	9ab0cfab84ded083718d3a4ff830726efd38869f-refs/branch-heads/3538@{#1002}
OS	Mac OS X

Reproducible on current release:

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

Yes, currently reproducible on dev and beta.

Additional Information

@NejcZdovc mentioned that this might be fixed once #1719 has been addressed. Once #1719 has been fixed, we'll need to go through the following and ensure that this case as been addressed as well.

[GeetaSarvadnya]

Verification Passed on

Brave	0.57.3 Chromium: 70.0.3538.67 (Official Build) dev (64-bit)
Revision	9ab0cfab84ded083718d3a4ff830726efd38869f-refs/branch-heads/3538@{#1002}
OS	Windows

ft.com:

Twitch

Verification Passed on

Brave	0.57.3 Chromium: 70.0.3538.67 (Official Build) dev (64-bit)
Revision	9ab0cfab84ded083718d3a4ff830726efd38869f-refs/branch-heads/3538@{#1002}
OS	Linux

Went through verification using the following build under macOS 10.13.6 x64 - PASSED

Brave	0.57.3 Chromium: 70.0.3538.67 (Official Build) dev (64-bit)
Revision	9ab0cfab84ded083718d3a4ff830726efd38869f-refs/branch-heads/3538@{#1002}
OS	Mac OS X