[Desktop] sometimes referrer doesn't display properly until page is reloaded - follow up to 8696

[LaurenWags]

Description

Found while testing #8696

Initial navigation to https://fmarier.github.io/brave-testing/referrer-spoofing.html shows expected value in "cross-origin navigation (redirected via meta)" iframe. However, if you navigate away (clicking on a specific button on this page) and back, "cross-origin navigation (redirected via meta)" now incorrectly shows blank referrer until you refresh the page.

Steps to Reproduce

1. Load https://fmarier.github.io/brave-testing/referrer-spoofing.html.
2. Notice that "cross-origin navigation (redirected via meta)" is showing the expected value.
3. Click on the "cross-origin navigation" link near the top of the page.
4. Click the back button.
5. Notice that "cross-origin navigation (redirected via meta)" is now showing a blank referrer instead of the expected value.

Actual result:

If you refresh the page, it will show the expected result.

Expected result:

Reproduces how often:

easily

Brave version (brave://version info)

Brave	1.12.108 Chromium: 84.0.4147.105 (Official Build) (64-bit)
Revision	a6b12dfad6663f13a7e16e9a42a6a4975374096b-refs/branch-heads/4147@{#943}
OS	macOS Version 10.14.6 (Build 18G3020)

Version/Channel Information:

• Can you reproduce this issue with the current release? 1.12.x yes
• Can you reproduce this issue with the beta channel? 1.13.x yes
• Can you reproduce this issue with the nightly channel? 1.14.x yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? no
• Does the issue resolve itself when disabling Brave Rewards? n/a
• Is the issue reproducible on the latest version of Chrome? n/a

Miscellaneous Information:

[fmarier]

cc @iefremov

[btlechowski]

Reproduced on

Brave	1.12.108 Chromium: 84.0.4147.105 (Official Build) (64-bit)
Revision	a6b12dfad6663f13a7e16e9a42a6a4975374096b-refs/branch-heads/4147@{#943}
OS	Ubuntu 18.04 LTS