[LBSE] Introduce RenderSVGModelObject aware geometry accessors in RenderLayerBacking

• Component: SVG
• Status: RESOLVED FIXED

[Nikolas Zimmermann]

Prepare RenderLayer/RenderLayerBacking for RenderSVGModelObject support:

Stop relying on renderBox() / downcast<RenderBox>(renderer()) to query layer geometry information, instead introduce helpers that take RenderLayerModelObject instead of RenderBox, to allow querying non-RenderBox derived renderers such as RenderSVGModelObject for geometry information.

[Nikolas Zimmermann]

Created attachment 451009 [details]
Patch, v1

[Rob Buis]

Comment on attachment 451009 [details]
Patch, v1

View in context: https://bugs.webkit.org/attachment.cgi?id=451009&action=review

> Source/WebCore/rendering/RenderLayerBacking.cpp:-3965
> -        return { };

Is this safe? Previously, non RenderBox would bail out. Is there now a chance the ASSERT_NOT_REACHED in rendererBorderBoxRect will be triggered?

[Nikolas Zimmermann]

(In reply to Rob Buis from comment #2)
> Comment on attachment 451009 [details]
> Patch, v1
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=451009&action=review
> 
> > Source/WebCore/rendering/RenderLayerBacking.cpp:-3965
> > -        return { };
> 
> Is this safe? Previously, non RenderBox would bail out. Is there now a
> chance the ASSERT_NOT_REACHED in rendererBorderBoxRect will be triggered?

It Is. The ASSERT_NOT_REACHED() is mainly to document that there is no missing edge case - verified by debug layout test runs.

There are no cases in RenderLayerBacking that had a bail-out, if the renderer type was not RenderBox, it was assumed to be RenderBox (and guaranteed by RenderLayer so far). transformMatrixForProperty() was the only method that had indeed a null check on renderBox() - but I cannot see how a non-RenderBox derived object can come there (only one callosities from within GraphicsLayers -- which are only ever created for RenderBox derived renderers, that create layers).

[Nikolas Zimmermann]

Committed r289213 (246898@trunk): <https://commits.webkit.org/246898@trunk>

[Radar WebKit Bug Importer]

<rdar://problem/88569054>