Use precomputed caller in the file save dialog title.

[goodov]

Use precomputed caller [1] from Chromium implementation to display the correct origin of a download in the save dialog.

1. https://source.chromium.org/chromium/chromium/src/+/main:chrome/browser/download/download_file_picker.cc;l=95-105;drc=7b865af5edfce7ef3b1cf82794845c6eb0c4f6f9

Resolves brave/brave-browser#42772

Submitter Checklist:

• I confirm that no security/privacy review is needed and no other type of reviews are needed, or that I have requested them
• There is a ticket for my issue
• Used Github auto-closing keywords in the PR description above
• Wrote a good PR/commit description
• Squashed any review feedback or "fixup" commits before merge, so that history is a record of what happened in the repo, not your PR
• Added appropriate labels (QA/Yes or QA/No; release-notes/include or release-notes/exclude; OS/...) to the associated issue
• Checked the PR locally:
  • npm run test -- brave_browser_tests, npm run test -- brave_unit_tests wiki
  • npm run presubmit wiki, npm run gn_check, npm run tslint
• Ran git rebase master (if needed)

Reviewer Checklist:

• A security review is not needed, or a link to one is included in the PR description
• New files have MPL-2.0 license header
• Adequate test coverage exists to prevent regressions
• Major classes, functions and non-trivial code blocks are well-commented
• Changes in component dependencies are properly reflected in gn
• Code follows the style guide
• Test plan is specified in PR before merging

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on
• All relevant documentation has been updated, for instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

[goodov]

@diracdeltas cleaning up "the site wants" or "the embedded iframe wants" can be done separately.

[diracdeltas]

@goodov thanks, though i'm not sure the existing text is correct anyway for iframes. for iframes, the text says "an embedded page ON $SITE" which implies that the $SITE is the main frame origin. if the site is actually the iframe origin, it should say "an embedded page AT $SITE".

so i'd prefer we at least fix the one line of text (on -> at) so it's correct

[goodov]

@goodov thanks, though i'm not sure the existing text is correct anyway for iframes. for iframes, the text says "an embedded page ON $SITE" which implies that the $SITE is the main frame origin. if the site is actually the iframe origin, it should say "an embedded page AT $SITE".

so i'd prefer we at least fix the one line of text (on -> at) so it's correct

Agree. Updated texts. cc @mkarolin

[diracdeltas]

thanks for taking this!

[bsclifton]

String reviewers ++

Beautiful 😄👍

[brave-builds]

Released in v1.75.104

[LaurenWags]

Verified with

Brave | 1.75.104 Chromium: 132.0.6834.46 (Official Build) nightly (arm64)
-- | --
Revision | 872376eea734257e6ab318c39373fbc82d3c4cba
OS | macOS Version 15.2 (Build 24C101)

See verification notes under https://github.com/brave/internal/issues/1238#issuecomment-2548577537.