Open
Description
Describe the issue
When serializing a FrozenCircuit
using Protos, it disregards the tags
attribute. Note that the json one works fine.
Explain how to reproduce the bug or problem
import cirq
import cirq_google.serialization.circuit_serializer as circuit_serializer
circuit = cirq.FrozenCircuit(tags=("foo"))
circuit_serializer.CIRCUIT_SERIALIZER.serialize(circuit)
Tell us the version of Cirq where this happens
1.6.0.dev20250519212157