dowjones promotional tabs not loading instantly after launch (taking ~30s)

[kjozwiak]

Description

When installing either the barrons or marketwatch promotion, you'll notice that it takes about ~30 seconds for the promotion tab to load after launch. Should be instant like in muon.

We had a similar issue with muon which was addressed by brave/browser-laptop#15067.

Steps to Reproduce

1. launch 0.55.20 Chromium: 70.0.3538.67 using Brave-Browser-dowjones-barrons.pkg
2. once installed, wait ~30 seconds until https://brave.com/dowjones-barrons loads in a new tab

Actual result:

Expected result:

It shouldn't take ~30 seconds for https://brave.com/dowjones-barrons to load in a new tab.

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

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

Reproducible on current release:

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

Not 100% sure as I haven't tried it with beta & dev but assuming they're having the same issue.

[GeetaSarvadnya]

Verification Passed on:

Brave	0.55.21 Chromium: 70.0.3538.77 (Official Build) (64-bit)
Revision	0f6ce0b0cd63a12cb4eccea3637b1bc9a29148d9-refs/branch-heads/3538@{#1039}
OS	Windows

• Verified https://brave.com/dowjones-barrons and https://brave.com/dowjones-marketwatch loads in a new tab immediately after install

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

Brave	0.55.21 Chromium: 70.0.3538.77 (Official Build) (64-bit)
Revision	0f6ce0b0cd63a12cb4eccea3637b1bc9a29148d9-refs/branch-heads/3538@{#1039}
OS	Mac OS X

• Verified https://brave.com/dowjones-barrons & https://brave.com/dowjones-marketwatch loads in a new tab immediately after install