De-duplicate the Cocoa-specific MediaPlayerPrivateRemote constructor
<rdar://problem/82031144>
Created attachment 435691 [details] Patch
Created attachment 435701 [details] Patch for landing
Committed r281157 (240607@main): <https://commits.webkit.org/240607@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 435701 [details].