// TestAllTypes and TestAllExtensions should have compatible wire formats,
// so if we serialize a TestAllTypes then parse it as TestAllExtensions
// it should work.
TestAllTypes message = TestUtil.getAllSet();
ByteString rawBytes = message.toByteString();
ExtensionRegistryLite registry_lite = TestUtil.getExtensionRegistryLite();
TestAllExtensionsLite message2 =
TestAllExtensionsLite.parseFrom(rawBytes, registry_lite);