PathGeometryCache warning message not exact

Here is a log message:

WARN  # 2018/10/30 10:07:29.377609000 # Job processor # Missing metric offset for edge rank=6 in path id=2533493833728226, calculated value is 0

• This message appears at each call to /vehicle_tracking/update_gps, it means the cache is constantly regenerated instead of being generated at path loading (at startup)
• At rank 6, if calculated metric offset is 0 it means there is a problem with the geometry and actually the metric offset calculation did not work, message should be like "require manual intervention"

DB: tpc_preprod

This issue might be related to #859 (closed)