static ProtobufException negativeSize()
    {
        return new ProtobufException(
                "CodedInput encountered an embedded string or message " +
                        "which claimed to have negative size.");
    }
Thrown when a protocol message being parsed is invalid in some way, e.g. it contains a malformed varint or a negative
byte length.

@author kenton@google.com Kenton Varda
@author David Yu
protostuff-core/src/main/java/io/protostuff/ProtobufException.java