feat(HLS): Improve HLS parsing time

[avelad]

Related to #5261

This PR delays the creation of the final urls of the segments so that they are not calculated in each media playlist parsing.

[github-actions]

Incremental code coverage: 100.00%

[avelad]

@theodab I added some asserts, can you approve the PR again? Thanks!

[theodab]

Oh, and another thing just occurred to me too.
This would have probably been better in the last PR, organizationally, but...

Could you add a comment in the JSDoc for shaka.util.ManifestParserUtils.resolveUris that explains that method is slow on SmartTV systems and should be delayed to after loading the manifest if possible? Or whatever the most accurate explanation for this is.
It'd be good to have documentation in the actual codebase, rather than just in GitHub comments.

[avelad]

Oh, and another thing just occurred to me too. This would have probably been better in the last PR, organizationally, but...

Could you add a comment in the JSDoc for shaka.util.ManifestParserUtils.resolveUris that explains that method is slow on SmartTV systems and should be delayed to after loading the manifest if possible? Or whatever the most accurate explanation for this is. It'd be good to have documentation in the actual codebase, rather than just in GitHub comments.

I added the comment