regression: delayed good path bug: trimmed_def_paths constructed

[Mark-Simulacrum]

Picked up in crater:

• https://crater-reports.s3.amazonaws.com/beta-1.64-2/beta-2022-08-09/gh/L1LLIAN.shorty-backend/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.64-2/beta-2022-08-09/gh/Niakr1s.rust_tree/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.64-2/beta-2022-08-09/gh/iiian.hundert/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.64-2/beta-2022-08-09/gh/jessaimaya.100_days_of_mogwai/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.64-2/beta-2022-08-09/reg/grep-index-0.0.1/log.txt

[compiler-errors]

I'm pretty certain this fixed by #99893

[compiler-errors]

I'll open a backport PR for this and nominate it

[apiraino]

WG-prioritization assigning priority (Zulip discussion).

@rustbot label -I-prioritize +P-medium

[pietroalbini]

Fix backported.