Add toSVGMissingGlyphElement(), and use it.
https://bugs.webkit.org/show_bug.cgi?id=120197

Reviewed by Andreas Kling.

As a step to clean-up static_cast<SVGXXX>, toSVGMissingGlyphElement() is added to clean-up
static_cast<SVGMissingGlyphElement*>.

* svg/SVGFontElement.cpp:
(WebCore::SVGFontElement::firstMissingGlyphElement):
(WebCore::SVGFontElement::ensureGlyphCache):
* svg/SVGMissingGlyphElement.h:
(WebCore::toSVGMissingGlyphElement):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154584 268f45cc-cd09-0410-ab3c-d52691b4dbfc
RenderLayerBacking::renderer() should return a reference.
<https://webkit.org/b/120280>

Reviewed by Anders Carlsson.

It's just a forwarding call to RenderLayer::renderer() which already returns a reference.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154585 268f45cc-cd09-0410-ab3c-d52691b4dbfc