Issues with reconstructing using images from GoPro Hero 4 Session

My GoPro Hero 4 Session apparently produces images with "Focal Length in 35mm" set to 1, which produces horrible results when trying to reconstruct a scene. When I change compute_focal to only use focal_35 > 1 and provide the sensor size (4.57mm) through sensor_data.json I get the results I expect.

I'm not really sure what has changed and where but my January uploads to Mapillary with this camera were fine while my uploads in September have issues. Because of build issues I haven't been able to check if older OpenSfM versions produce the same issues, and I don't have older images I can use to check for changes in the exif data.

Is it reasonable for OpenSfM to ignore exif data if the 35mm focal length is reported as <= 1?

Example Mapillary image with issues: https://www.mapillary.com/app/?lat=59.9627934&lng=11.0542162&z=17&pKey=1035824187167841&focus=photo

Start at the compute_focal logic and sensor_data.json handling mentioned in the issue, then inspect how the GoPro EXIF value is used during reconstruction. Compare the reported focal-length behavior with the suggested <=1 condition and sensor size. Done means the invalid 35mm value no longer produces incorrect reconstruction results, with the behavior verified against the example image if available.