ReplayGainInfo: add method Get()

src/ReplayGainInfo.hxx

@@ -56,6 +56,10 @@ struct ReplayGainInfo {
 			tuples[REPLAY_GAIN_TRACK].IsDefined();
 	}
 
+	const ReplayGainTuple &Get(ReplayGainMode mode) const {
+		return tuples[mode];
+	}
+
 	void Clear() {
 		tuples[REPLAY_GAIN_ALBUM].Clear();
 		tuples[REPLAY_GAIN_TRACK].Clear();

src/decoder/Bridge.cxx

@@ -597,7 +597,7 @@ DecoderBridge::SubmitReplayGain(const ReplayGainInfo *new_replay_gain_info)
 			if (rgm != REPLAY_GAIN_ALBUM)
 				rgm = REPLAY_GAIN_TRACK;
 
-			const auto &tuple = new_replay_gain_info->tuples[rgm];
+			const auto &tuple = new_replay_gain_info->Get(rgm);
 			const auto scale =
 				tuple.CalculateScale(replay_gain_preamp,
 						     replay_gain_missing_preamp,

src/filter/plugins/ReplayGainFilterPlugin.cxx

@@ -140,7 +140,7 @@ ReplayGainFilter::Update()
 {
 	unsigned volume = PCM_VOLUME_1;
 	if (mode != REPLAY_GAIN_OFF) {
-		const auto &tuple = info.tuples[mode];
+		const auto &tuple = info.Get(mode);
 		float scale = tuple.CalculateScale(replay_gain_preamp,
 						   replay_gain_missing_preamp,
 						   replay_gain_limit);