Cache temporary link for url resolution

[mourner]

Closes #8032. Avoids unnecessary GC freezes when collecting unattached DOM objects by caching the link element for URL resolution. @poletani can you check if this fixes your issue?

Launch Checklist

• briefly describe the changes in this PR
• write tests for all new functionality we don't test browser-dependent methods
• document any changes to public APIs
• post benchmark scores
• manually test the debug page

[ryanhamley]

Looks good to me

[ryanhamley]

I think the underlying issue is that the anchor's href property was saved to an options object in geojson_source._updateWorkerData then a different property in the options object was used in dispatching the update to a worker. Since we reuse workers, it seems like the options object was never being garbage collected and in turn the <a> tags weren't being garbage collected. Either way, this should fix the issue.

[mourner]

@ryanhamley a.href is a string (a primitive value), so it shouldn't have any connection to the anchor. I think I misread the original report — the DOM object was indeed garbage collected, but not immediately because browsers prefer to do that in batches, and apparently if there were a ton of these objects to collect during a garbage sweep, it could cause micro-stutters.

[poletani]

@mourner unfortunately now I am unable to check it (I'll try later just to be sure), but it appears to me like the ideal solution. Thanks a lot for fixing it!

[poletani]

@mourner I can confirm that the number of DOM nodes remains constant under the same test method, using the new fix.

[pakastin]

Perfect, this was a huge issue for me! Great work! 👌