Yes and no.
The warnings are new but they only warn you about stuff that were always happening since 1.0.0 (from that version onwards, vehicle are allowed to perform emergency deceleration).
Some of those decelerations are due to bugs (discovered since introducing the warning).
If fixed some of the bugs this week so just upgrade to the very latest version.
I think we'll get rid of most of the warnings by the time 1.1 is released in december.
You can supress the warning by setting option
--emergencydecel.warning-threshold 1.1
regards,
Jakob
btw: your sumo version specifier seems wrong because the warning was introduced 7 days ago but the commit hash is from 24 days ago.
