grpc: Update protobuf regenrate script (#4177)

- Pull in protobuf repo since one of our protos pulls in duration.proto
- Update grpc_testing/messages.pb.go to pull in a recent change

interop/grpc_testing/messages.pb.go

@@ -1185,8 +1185,8 @@ type LoadBalancerAccumulatedStatsResponse struct {
 	//
 	// Deprecated: Do not use.
 	NumRpcsFailedByMethod map[string]int32 `protobuf:"bytes,3,rep,name=num_rpcs_failed_by_method,json=numRpcsFailedByMethod,proto3" json:"num_rpcs_failed_by_method,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"varint,2,opt,name=value,proto3"`
-	// Per-method RPC statistics.  The key is the full method path; i.e.
-	// "/proto.package.ServiceName/MethodName".
+	// Per-method RPC statistics.  The key is the RpcType in string form; e.g.
+	// 'EMPTY_CALL' or 'UNARY_CALL'
 	StatsPerMethod map[string]*LoadBalancerAccumulatedStatsResponse_MethodStats `protobuf:"bytes,4,rep,name=stats_per_method,json=statsPerMethod,proto3" json:"stats_per_method,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
 }
 

regenerate.sh

@@ -40,6 +40,9 @@ echo "go install cmd/protoc-gen-go-grpc"
 echo "git clone https://github.com/grpc/grpc-proto"
 git clone --quiet https://github.com/grpc/grpc-proto ${WORKDIR}/grpc-proto
 
+echo "git clone https://github.com/protocolbuffers/protobuf"
+git clone --quiet https://github.com/protocolbuffers/protobuf ${WORKDIR}/protobuf
+
 # Pull in code.proto as a proto dependency
 mkdir -p ${WORKDIR}/googleapis/google/rpc
 echo "curl https://raw.githubusercontent.com/googleapis/googleapis/master/google/rpc/code.proto"
@@ -87,6 +90,7 @@ for src in ${SOURCES[@]}; do
     -I"." \
     -I${WORKDIR}/grpc-proto \
     -I${WORKDIR}/googleapis \
+    -I${WORKDIR}/protobuf/src \
     -I${WORKDIR}/istio \
     ${src}
 done
@@ -97,6 +101,7 @@ for src in ${LEGACY_SOURCES[@]}; do
     -I"." \
     -I${WORKDIR}/grpc-proto \
     -I${WORKDIR}/googleapis \
+    -I${WORKDIR}/protobuf/src \
     -I${WORKDIR}/istio \
     ${src}
 done