Fix WavDecoder::total_duration.

[IohannRabeson]

It was ignoring the channels count.

[roderickvd]

D'oh! Pointy hat to me, good one. I probably copied the same mistake in the lewton FLAC decoder too:

rodio/src/decoder/flac.rs

Line 50 in 8fd0337

let sample_rate = sample_rate as u64;

[IohannRabeson]

Ok, I'm checking and I will fix it.

[dvdsk]

D'oh! Pointy hat to me, good one. I probably copied the same mistake in the lewton FLAC decoder too:

you've got this (very nice) comment there that points to the opposite:

        // `samples` in FLAC means "inter-channel samples" aka frames
        // so we do not divide by `self.channels` here.

[IohannRabeson]

I renamed sample_rate to data_rate and I removed the commit that was modifying FlacDecoder.

[roderickvd]

D'oh! Pointy hat to me, good one. I probably copied the same mistake in the lewton FLAC decoder too:

you've got this (very nice) comment there that points to the opposite:

        // `samples` in FLAC means "inter-channel samples" aka frames
        // so we do not divide by `self.channels` here.

🤦‍♂️ I will go to bed now 😄

[dvdsk]

I'm gonna go and add some integration tests to prevent this from ever regressing. Looks good to merge for me

[dvdsk]

🤦‍♂️ I will go to bed now 😄

I should follow your example, I just spend some time writing total duration tests before realizing I already did that... three days ago (to be merged as part of #697).