[CR126] Downloads page is inherited from upstream as the warning buttons are not shown when dangerous files are downloaded

[MadhaviSeelam]

Description

[Edit: including normal file download buttons as well] Found while testing https://github.com/brave/brave-browser/issues/38556. When tested to verify downloading a malicious file via https://testsafebrowsing.appspot.com/s/content.exe, Remove from list and Keep dangerous file buttons are not shown in the brave://downloads page. And the page is inherited from chromium as chrome://downloads page shown same. Downloaded normal files and Pause, Cancel, Resume & Retry buttons are not shown when regular files (not malicious) are downloaded

Steps to reproduce

1. Install
2. launch Brave
3. open https://testsafebrowsing.appspot.com/s/content.exe in a new tab
4. open https://ubuntu.com/download/desktop/thank-you?version=24.04&architecture=amd64&lts=true
5. click Save
6. open brave://downloads page

Actual result

Remove from list and Keep dangerous file buttons are not shown

example	example	example	example

Expected result

Remove from list and Keep dangerous file buttons should be shown

example	example	example

Reproduces how often

Easily reproduced

Brave version (brave://version info)

Brave | 1.68.55 Chromium: 126.0.6478.17 (Official Build) nightly (64-bit)
-- | --
Revision | 5a7678f3d6d2c339a12dd6a91d6369c04cd34287
OS | Windows 11 Version 23H2 (Build 22631.3593)

Channel information

• [ ] release (stable)
• [ ] beta
• [X] nightly

Reproducibility

• [ ] with Brave Shields disabled
• [ ] with Brave Rewards disabled
• [ ] in the latest version of Chrome

Miscellaneous information

@rebron @emerick cc: @brave/qa-team

[emerick]

This change is due to the kImprovedDownloadPageWarnings which is now enabled by default. I'm pushing a PR that disables that setting which restores the old UI, but the buttons seem a little bit squared off to me. Not sure if that's acceptable or not. Might need someone like @fallaciousreasoning to take a look, if not.

This is what they look like with my change

[fallaciousreasoning]

@emerick that's fine - @aguscruiz squared all the squircles :D

[kjozwiak]

The above requires 1.67.101 or higher for 1.67.x verification 👍

[MadhaviSeelam]

Verification PASSED using

Brave | 1.67.101 Chromium: 126.0.6478.26 (Official Build) beta (64-bit)
-- | --
Revision | a561f4b53cdb831888e5cd702d2b8f9598c00f50
OS | Windows 11 Version 23H2 (Build 22631.3672)

Verified using the STR from issue description https://github.com/brave/brave-browser/issues/38657#issue-2322105488

Confirmed Remove from list and Keep dangerous file buttons are shown for dangerous file downloads Confirmed Download page buttons (Pause, Cancel, Resume, Retry) are shown and working as expected

example	example	example	example	example	example