Previous artwork isn't cleared when NowPlaying info doesn't contain an artwork

• Component: New Bugs
• Status: RESOLVED FIXED

[Jean-Yves Avenard [:jya]]

Previous artwork isn't cleared when no NowPlaying info doesn't contain an artwork

[Jean-Yves Avenard [:jya]]

<rdar://76044544>

[Jean-Yves Avenard [:jya]]

Created attachment 424850 [details]
Patch

[Jean-Yves Avenard [:jya]]

Created attachment 424854 [details]
Patch

[Jean-Yves Avenard [:jya]]

Created attachment 424860 [details]
Patch

[Eric Carlson]

Comment on attachment 424860 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=424860&action=review

> Source/WebCore/platform/audio/cocoa/MediaSessionManagerCocoa.mm:322
> +    MRMediaRemoteSetNowPlayingInfoWithMergePolicy(info.get(), MRMediaRemoteMergePolicyReplace);

This is fine for now, but I assume it is more expensive so we should see if passing MRMediaRemoteMergePolicyUpdate when the artwork doesn't change works.

[EWS]

Committed r275360: <https://commits.webkit.org/r275360>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 424860 [details].

[Jean-Yves Avenard [:jya]]

(In reply to Eric Carlson from comment #5)
> Comment on attachment 424860 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=424860&action=review
> 
> > Source/WebCore/platform/audio/cocoa/MediaSessionManagerCocoa.mm:322
> > +    MRMediaRemoteSetNowPlayingInfoWithMergePolicy(info.get(), MRMediaRemoteMergePolicyReplace);
> 
> This is fine for now, but I assume it is more expensive so we should see if
> passing MRMediaRemoteMergePolicyUpdate when the artwork doesn't change works.

The recommendation to use the replace policy came from the MR team and I specifically asked about the extra overhead due to this. 

But the update policy is only designed to publish one field at the time and re-use and only replace the fields we've already passed. 

The way webkit uses MR is by publishing all its info each time, it never updates as such.

Also, looking at the MR source code update vs replace doesn't add any overhead really. It's a simple test that either use the CFDictionary it receives or update the cached one with the new values found in the new one.
Ultimately you end up with a complete CFDictionary of things being sent to the MR listeners. 

What we could do however is stop sending the artwork all the time and use the update policy instead.