[GPU Process] Add the class 'SourceImage' to represent variants of image

[Said Abou-Hallawa]

FEImage has already an std::variant named 'SourceImage' to represent variants of image. The Pattern needs a similar structure; see bug 232411. So the plan is replace FEImage::SourceImage with the new class. Then make bug 232411 uses it as well.

[Said Abou-Hallawa]

Created attachment 449719 [details]
Patch

[Said Abou-Hallawa]

Created attachment 449720 [details]
Patch

[Said Abou-Hallawa]

Created attachment 449722 [details]
Patch

[Cameron McCormack (:heycam)]

Comment on attachment 449722 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=449722&action=review

> Source/WebCore/ChangeLog:8
> +        Before the existence of GPUProces we used to make some drawing on an 

"GPUProcess"

s/make some drawing/do some drawing/

> Source/WebCore/ChangeLog:10
> +        NativeImage. With GPUProces, this will require bouncing the NativeImage 

"GPUProcess"

> Source/WebCore/ChangeLog:11
> +        between WebPorcess and GPUProcess at least two times. To make this scenario 

"WebProcess"

> Source/WebCore/ChangeLog:12
> +        efficient, a new class called SourceImage' will be introduced. The purpose

Stray (or missing) apostrophe.

> Source/WebCore/platform/graphics/SourceImage.cpp:74
> +    auto imageBuffer = ImageBuffer::create(nativeImage->size(), RenderingMode::Unaccelerated, 1, DestinationColorSpace::SRGB(), PixelFormat::BGRA8);

If canvas patterns will use this class, then they'll need a way to specify the color space when creating the ImageBuffer, so that we don't always convert to sRGB.

[Said Abou-Hallawa]

Created attachment 449728 [details]
Patch

[EWS]

Committed r288412 (246303@main): <https://commits.webkit.org/246303@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 449728 [details].

[Radar WebKit Bug Importer]

<rdar://problem/87931919>