This will be done by subclassing 'PixelBuffer' to a new class named 'ShareablePixelBuffer' and subclassing 'ImageBufferAllocator' to a new class named 'ImageBufferShareableAllocator'. FilterResults takes a std::unique_ptr< ImageBufferAllocator> as input. It passes a reference to it to every FilterImage it creates. FilterImage will use it to create its buffers.
<rdar://problem/94118129>
Pull request: https://github.com/WebKit/WebKit/pull/1291
Committed r295372 (251380@main): <https://commits.webkit.org/251380@main> Reviewed commits have been landed. Closing PR #1291 and removing active labels.