Brave UA whitelist only applies to top level page loads

[kjozwiak]

Test plan

#10904 (comment)

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- Did you search for similar issues before submitting this one?

Yes

- Describe the issue you encountered:

Brave's UA whitelist only applies to top level page loads and not sub resources. I believe it's this line in the code:

https://github.com/brave/browser-laptop/blob/master/js/data/siteHacks.js#L46

- Platform (Win7, 8, 10? macOS? Linux distro?):

macOS 10.12.16 x64 - Reproduced
Win 10 x64 - Reproduced

- Brave Version (revision SHA):

Brave: 0.18.26
rev: 67f2568
Muon: 4.3.15
libchromiumcontent: 60.0.3112.101

- Steps to reproduce:

1. load adobe.com within Brave
2. open the developer tools via "option + command + I"
3. select the "Network" tab and reload adobe.com via "command + r"
4. select on the first resource and you'll notice the correct Brave Chrome/60.0.3112.101 UA
5. select another resource that's underneath the first one and is from Host:www.adobe.com

You'll notice that the incorrect UA is being used.

- Actual result:

Only the first resource (top level) is correctly using the UA.

- Expected result:

The correct UA should be applied to every resource that's from the whitelist domain.

- Will the steps above reproduce in a fresh profile? If not what other info can be added?

Yes

- Is this an issue in the currently released version?

#10614 was supposed to fix this issue, however it only partially fixed the problem.

- Can this issue be consistently reproduced?

Yes

- Screenshot if needed:

Correct Example:

Incorrect Example:

- Any related issues:

#10614

[LaurenWags]

Verified on MacOS: