[MediaStream][Mac] Use AVCapturePreview interfaces for camera/microphone rendering

[Eric Carlson]

Use AVCaptureAudioPreview and AVCaptureVideoPreviewLayer for previewing audio and video when possible.

[Radar WebKit Bug Importer]

<rdar://problem/29297727>

[Eric Carlson]

Created attachment 294988 [details]
Proposed patch.

[Eric Carlson]

Created attachment 294991 [details]
Updated patch.

[Eric Carlson]

Created attachment 294995 [details]
Updated patch.

[Jer Noble]

Comment on attachment 294995 [details]
Updated patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=294995&action=review

r=me with minor nit.

> Source/WebCore/platform/mediastream/MediaStreamTrackPrivate.cpp:185
> +RealtimeMediaSourcePreview* MediaStreamTrackPrivate::preview()
> +{
> +    if (m_preview)
> +        return m_preview.get();
> +
> +    m_preview = m_source->preview();
> +    return m_preview.get();
> +}
> +

Is there any reason to cache the value of m_source->preview() at this level? m_source can never change, but it may want to swap out the preview layer (in some future patch), and caching this here would make that harder.

[Eric Carlson]

(In reply to comment #5)
> Comment on attachment 294995 [details]
> Updated patch.
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=294995&action=review
> 
> r=me with minor nit.
> 
> > Source/WebCore/platform/mediastream/MediaStreamTrackPrivate.cpp:185
> > +RealtimeMediaSourcePreview* MediaStreamTrackPrivate::preview()
> > +{
> > +    if (m_preview)
> > +        return m_preview.get();
> > +
> > +    m_preview = m_source->preview();
> > +    return m_preview.get();
> > +}
> > +
> 
> Is there any reason to cache the value of m_source->preview() at this level?
> m_source can never change, but it may want to swap out the preview layer (in
> some future patch), and caching this here would make that harder.

I will commit this patch as-is, but we can talk about changing this in another patch.

[WebKit Commit Bot]

Comment on attachment 294995 [details]
Updated patch.

Clearing flags on attachment: 294995

Committed r208851: <http://trac.webkit.org/changeset/208851>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.