Project: mesos
Issue MESOS-3284: JSON representation of Protobuf should use base64 encoding for 'bytes' fields.
Currently we encode 'bytes' fields as UTF-8 strings, which is lossy for binary data due to invalid byte sequences! In order to encode binary data in a lossless fashion, we can encode 'bytes' fields in base64. Note that this is also how proto3 does its encoding (see [here|https://developers.google.com/protocol-buffers/docs/proto3?hl=en#json]), so this would make migration easier as well.
Story points: 3