Use better fallback URLs when calling AVScanFile().
Windows Attachment Services defaults to treating downloads of data: URLs
and other unknown URL schemes as being trustworthy. In addition, source URLs
that are longer than INTERNET_MAX_URL_LENGTH could also cause the
mark-of-the-web to not be applied.
This CL attempts to mitigate these cases by changing base_file_win.cc to
use the referrer URL if one is available and is either http or https.
Furthermore, if the source URL is too long or is empty,
quarantine_win.cc will use the safe fallback "about:internet" as the
source URL.
In addition, quarantine_win.cc now also sets the Referrer field if a
valid referrer is found.
BUG=601538
Review-Url: https://codereview.chromium.org/2025103002
Cr-Commit-Position: refs/heads/master@{#421000}
5 files changed
