In the 2.1.0 jar, google/api/endpoint.proto contains a repeated string features = 4, however the corresponding Java class file doesn't have any of the methods corresponding to this field.

Steps to reproduce

$ mkdir tmp && cd tmp
$ curl https://repo1.maven.org/maven2/com/google/api/grpc/proto-google-common-protos/2.1.0/proto-google-common-protos-2.1.0.jar -O
$ less google/api/endpoint.proto   # observe Endpoint has a field features
$ javap  com.google.api.Endpoint | grep -i feature | wc -l
0 

It looks like getters for features are not there. Seemingly the code has been generated with a different version of the protos.