[LBSE] Extend overflow/clip rect handling for SVG layers

• Component: SVG
• Status: RESOLVED FIXED

[Nikolas Zimmermann]

Prepare RenderLayer/RenderLayerBacking for RenderSVGModelObject support:

Allow to re-use overflow clipping logic for certain type of SVG containers, deriving from RenderSVGModelObject, namely: RenderSVGViewportContainer / RenderSVGResourceMarker (RenderSVGRoot uses the same logic, but through RenderReplaced: it doesn't derived from RenderSVGModelObject). Once all things are in place, the SVG overflow logic is gone, replaced in all areas by the shared CSS one.

[Nikolas Zimmermann]

Created attachment 451013 [details]
Patch, v1

[Rob Buis]

Comment on attachment 451013 [details]
Patch, v1

This could be more efficient in the case LAYER_BASED_SVG_ENGINE is not enabled, but since we want to convert to it given all the benefits I think it is no problem.

[Nikolas Zimmermann]

(In reply to Rob Buis from comment #2)
> Comment on attachment 451013 [details]
> Patch, v1
> 
> This could be more efficient in the case LAYER_BASED_SVG_ENGINE is not
> enabled, but since we want to convert to it given all the benefits I think
> it is no problem.

I also thought about caching the 'is<RenderBox>(renderer())' somewhere, but this smells like a pre-mature optimization that looks cheaper on first sight, but without instruction level profiling I wouldn't be on it.

[Nikolas Zimmermann]

Committed r289204 (246890@trunk): <https://commits.webkit.org/246890@trunk>

[Radar WebKit Bug Importer]

<rdar://problem/88564886>