I'm not sure as I'm new with servo but shouldn't the new function ```parse_opt_prefs``` be in ```prefs.rs``` instead of ```opts.rs``` ?
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#14842
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Source-Repo: https://github.com/servo/servo
Source-Revision: 42e28bf7e59e0c7fab7163326d7374d1c4e268d1