This changes text marshaling to avoid unknown fields by default
and instead adds an option so that unknown fields be emitted.
This ensures that the default marshal/unknown can round-trip.
Change-Id: I85c84ba6ab7916d538ec6bfd4e9d399a8fcba14e
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/195778
Reviewed-by: Herbie Ong <herbie@google.com>
The use of internal/cmd/conformance/conformance.sh means that the test
is not hermetic since the script uses the system version of go,
rather than the specific versions chosen by integration_test.go.
Change the way the conformance test is invoked by turning it
into a Go unit test that integration_test.go can directly call.
Change-Id: I37d23341e1eda984f23f78757a38e862e5fac3d4
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/190518
Reviewed-by: Herbie Ong <herbie@google.com>