fix: Don't use copyStyleSheets with documentPIP

[beaufortfrancois]

Document Picture-in-Picture API owners are removing copyStyleSheets option as it can be done in JavaScript. This PR removes this option and copy all style sheets internally to the PiP window.

@mister-ben Please review.

[codecov]

Codecov Report

Merging #8314 (77becf3) into main (6c4997d) will increase coverage by 0.04%.
The diff coverage is 57.14%.

❗ Current head 77becf3 differs from pull request most recent head 873d0c7. Consider uploading reports for the commit 873d0c7 to get more accurate results

@@            Coverage Diff             @@
##             main    #8314      +/-   ##
==========================================
+ Coverage   82.57%   82.62%   +0.04%     
==========================================
  Files         112      113       +1     
  Lines        7497     7578      +81     
  Branches     1809     1820      +11     
==========================================
+ Hits         6191     6261      +70     
- Misses       1306     1317      +11     

Impacted Files	Coverage Δ
src/js/player.js	90.89% <ø> (+0.07%)	⬆️
src/js/utils/dom.js	64.28% <57.14%> (-0.92%)	⬇️

... and 25 files with indirect coverage changes

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[mister-ben]

Thanks for the update. I'm not really sure I agree that it makes any more sense for each player library to manage copying stylesheets, but if that's how it is...

The copy method would ideally not be exposed on the player, as the inline comment. We'll need to address test coverage too.

[beaufortfrancois]

The copy method would ideally not be exposed on the player, as the inline comment. We'll need to address test coverage too.

I've moved it and added some basic tests. Let me know if that looks good to you.

[beaufortfrancois]

(gentle ping)

[mister-ben]

@beaufortfrancois Tahnks for the updates. I've been out for a couple of weeks, back now and will check this week.

[mister-ben]

We'll need to do something with this as Chrome Canary already remove copyStylesheets. @beaufortfrancois any comments re the suggested changes to make sure the order of stylesheets is preserved?

[beaufortfrancois]

Thank you @mister-ben for all your feedback!

[mister-ben]

Thanks!