Support 'paint-order' from SVG2.

LayoutTests/svg/W3C-SVG2/paintorder.svg

Index: LayoutTests/svg/W3C-SVG2/paintorder.svg
diff --git a/LayoutTests/svg/W3C-SVG2/paintorder.svg b/LayoutTests/svg/W3C-SVG2/paintorder.svg
new file mode 100644
index 0000000000000000000000000000000000000000..489554a1b28b3253706732425217538ac5d6caca
--- /dev/null
+++ b/LayoutTests/svg/W3C-SVG2/paintorder.svg
@@ -0,0 +1,37 @@
+<svg viewBox="-10 -10 280 220" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">

[pdr., 2013/05/03 17:58:29]

Typically the tests in the W3C-*/ directories are official tests from the W3C,
but that's not a fixed rule by any means. If you plan to upstream this test to
the W3C, this is a great location. Otherwise, I would suggest putting this in
LayoutTests/svg/paintorder, but this is up to your judgement.

Could we add an additional test for dynamic values, to show that changing the
paint order causes the appropriate repaint to occur? There should be examples of
this type of test in LayoutTests/svg/repaint.

+	<defs>
+		<marker id="m" refX="5" refY="5" viewBox="0 0 10 10" overflow="visible">
+			<circle cx="5" cy="5" r="3" fill="black" stroke="black" fill-opacity="0.5"/>
+		</marker>
+		<svg id="poly" viewBox="-10 -10 420 420">
+			<polygon points="50 50 50 350 350 350 250 200" fill="blue" stroke="lime" stroke-width="50" style="marker: url(#m)" stroke-opacity="0.5"/>
+		</svg>
+	</defs>
+	
+	<use xlink:href="#poly" width="50" height="50"/>
+	<use xlink:href="#poly" style="paint-order: normal" width="50" height="50" x="50"/>
+	
+	<g transform="translate(0,50)">
+		<use xlink:href="#poly" style="paint-order: fill" width="50" height="50" x="0"/>
+		<use xlink:href="#poly" style="paint-order: fill stroke" width="50" height="50" x="50"/>
+		<use xlink:href="#poly" style="paint-order: fill stroke markers" width="50" height="50" x="100"/>
+		<use xlink:href="#poly" style="paint-order: fill markers" width="50" height="50" x="150"/>
+		<use xlink:href="#poly" style="paint-order: fill markers stroke" width="50" height="50" x="200" />
+	</g>
+	
+	<g transform="translate(0,100)">
+		<use xlink:href="#poly" style="paint-order: stroke" width="50" height="50" x="0"/>
+		<use xlink:href="#poly" style="paint-order: stroke fill" width="50" height="50" x="50"/>
+		<use xlink:href="#poly" style="paint-order: stroke fill markers" width="50" height="50" x="100"/>
+		<use xlink:href="#poly" style="paint-order: stroke markers" width="50" height="50" x="150"/>
+		<use xlink:href="#poly" style="paint-order: stroke markers fill" width="50" height="50" x="200"/>
+	</g>
+	
+	<g transform="translate(0,150)">
+		<use xlink:href="#poly" style="paint-order: markers" width="50" height="50" x="0"/>
+		<use xlink:href="#poly" style="paint-order: markers stroke" width="50" height="50" x="50"/>
+		<use xlink:href="#poly" style="paint-order: markers stroke fill" width="50" height="50" x="100"/>
+		<use xlink:href="#poly" style="paint-order: markers fill" width="50" height="50" x="150"/>
+		<use xlink:href="#poly" style="paint-order: markers fill stroke" width="50" height="50" x="200"/>
+	</g>
+</svg>