Bugfix/ID3 Decoding On Play Station 4

[agajassi]

This PR will...

On PS4, TextDecoder is defined but it is partially implemented and does not function properly. This will force manual decoding approach for PS4 platform in utf8ArrayToStr function.

Why is this Pull Request needed?

It is necessary for private id3s to be correctly decoded and converted on Play Station 4 platform.

Are there any points in the code the reviewer needs to double check?

Resolves issues: #6041

Checklist

• changes have been done against master branch, and PR does not conflict
• new unit / functional tests have been added (whenever applicable)
• API or design changes are documented in API.md

[robwalch]

Would this be a good candidate for feature detection? Rather than check userAgent, can we do a check the first time getTextDecoder() is called and set a flag like supportsUtf8Decoding?

Can you work out what byte(s) would make for such a test? Here's an example that checks decoded length. It assumes the decoder can be reused (might need to create a new one for the test).

let supportsUtf8Decoding?: boolean;
let decoder: TextDecoder;

function getTextDecoder() {
  if (supportsUtf8Decoding === false) {
    return;
  }
  if (!decoder && typeof self.TextDecoder !== 'undefined') {
    decoder = new self.TextDecoder('utf-8');
  }
  if (supportsUtf8Decoding === undefined) {
    // not sure what the test should look like
    if (decoder.decode(new Uint8Array([0xf9])).length === 0) {
      supportsUtf8Decoding = false;
      decoder = undefined;
      return;
    }
  }

[agajassi]

@robwalch I tried various set of byte sequences as a test. I keep getting inconsistent results every time I run it on PS4. It will evaluate as true and if you reload the page, second time it will be false. So far I cannot come up with a reliable byte sequence to use for feature testing.

I tried these:

• '€'
  new Uint8Array([0xE2, 0x82, 0xAC]);
• 'testñtest'
  new Uint8Array([0x74, 0x65, 0x73, 0x74, 0xC3, 0xB1, 0x74, 0x65, 0x73, 0x74]);
• 'ID3......?'
  new Uint8Array([73, 68, 51, 4, 0, 0, 0, 0, 0, 63])
• 'Hello é€😀'
  new Uint8Array([0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0xC3, 0xA9, 0xE2, 0x82, 0xAC, 0xF0, 0x9F, 0x98, 0x80]);

As of now I have not seen this type of issue on any other devices (and I work and test with so many set top boxes and tvs). To me trying to make this generic by using feature detection does not seem to be beneficial.

[robwalch]

Thanks for trying and going down the rabbit hole on this.

I see the UA workaround in other MSE players so let's go with it!

[robwalch]

For this to go into 1.4.14, we need the change in patch/v1.4.x. After this is approved and merged, please cherry-pick into that branch and open another PR.