proto: use vtprotobuf optimized functions when available

Envoy tracking issue:
envoyproxy/go-control-plane#824

This will be a NOP until go-control-plane completes ^. Once that
happens, we will get the optimizations for free

Author: howardjohn

pilot/pkg/util/protoconv/protoconv.go

@@ -28,7 +28,7 @@ import (
 
 // MessageToAnyWithError converts from proto message to proto Any
 func MessageToAnyWithError(msg proto.Message) (*anypb.Any, error) {
-	b, err := proto.MarshalOptions{Deterministic: true}.Marshal(msg)
+	b, err := marshal(msg)
 	if err != nil {
 		return nil, err
 	}
@@ -39,6 +39,16 @@ func MessageToAnyWithError(msg proto.Message) (*anypb.Any, error) {
 	}, nil
 }
 
+func marshal(msg proto.Message) ([]byte, error) {
+	if vt, ok := msg.(vtStrictMarshal); ok {
+		// Attempt to use more efficient implementation
+		// "Strict" is the equivalent to Deterministic=true below
+		return vt.MarshalVTStrict()
+	}
+	// If not available, fallback to normal implementation
+	return proto.MarshalOptions{Deterministic: true}.Marshal(msg)
+}
+
 // MessageToAny converts from proto message to proto Any
 func MessageToAny(msg proto.Message) *anypb.Any {
 	out, err := MessageToAnyWithError(msg)
@@ -82,3 +92,8 @@ func UnmarshalAny[T any](a *anypb.Any) (*T, error) {
 	}
 	return any(dst).(*T), nil
 }
+
+// https://github.com/planetscale/vtprotobuf#available-features
+type vtStrictMarshal interface {
+	MarshalVTStrict() ([]byte, error)
+}