https://bugs.webkit.org/show_bug.cgi?id=88188

Patch by Frédéric Wang <fred.wang@free.fr> on 2014-01-15
Reviewed by Chris Fleizach.

Source/WebCore:

When HTML and MathML are used as foreign objects of an SVG image, it is
important for Web authors to be able to specify a fallback content for
SVG-only readers or browsers without MathML support. We rely on the
requiredExtensions for that purpose and we use the XHTML/MathML
namespaces as suggested in SVG Tiny 1.2 and implemented in Gecko.

Tests: svg/custom/conditional-processing-1.svg
       svg/custom/conditional-processing-2.html
       svg/dom/SVGTests.html

* svg/SVGSwitchElement.cpp: Remove an incorrect FIXME comment and replace it with a reference to bug 74749.
(WebCore::SVGSwitchElement::childShouldCreateRenderer):
* svg/SVGTests.cpp: Check if the list of required extensions contains only the XHTML/MathML namespaces.
(WebCore::SVGTests::hasExtension):
(WebCore::SVGTests::isValid):

LayoutTests:

conditional-processing-1 verifies that indeed a renderer object is only
created for the first "valid" SVG element of a <switch>, contrary to
what an incorrect FIXME comment said. conditional-processing-2 verifies
that the <switch> takes into account XHTML and MathML namespaces in the
requiredExtensions attribute to decide which SVG element is "valid".
SVGTests.html verifies the SVGTests interface of SVG DOM: three
SVGStringList attributes (already tested in svg/dom/SVGStringList.html)
and the hasExtension() function.

* svg/custom/conditional-processing-1-expected.svg: Added.
* svg/custom/conditional-processing-1.svg: Added.
* svg/custom/conditional-processing-2-expected.html: Added.
* svg/custom/conditional-processing-2.html: Added.
* svg/dom/SVGTests-expected.txt: Added.
* svg/dom/SVGTests.html: Added.
* svg/dom/script-tests/SVGTests.js: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162083 268f45cc-cd09-0410-ab3c-d52691b4dbfc