Added Skia turbulence filter to Webkit.

LayoutTests/css3/filters/effect-reference.html

Index: LayoutTests/css3/filters/effect-reference.html
diff --git a/LayoutTests/css3/filters/effect-reference.html b/LayoutTests/css3/filters/effect-reference.html
index e809b469ceb8511a97008c260f40d86cc47f5db1..9d08e737b7cbbcde42379a279dad6c7af43c23f7 100644
--- a/LayoutTests/css3/filters/effect-reference.html
+++ b/LayoutTests/css3/filters/effect-reference.html
@@ -52,6 +52,9 @@
     <filter id="flood" color-interpolation-filters="sRGB">
       <feFlood flood-color="green"/>
     </filter>
+    <filter id="turbulence" color-interpolation-filters="sRGB">
+      <feTurbulence type="turbulence" baseFrequency="0.05" numOctaves="2"/>
+    </filter>
   </defs>
 </svg>
 <style>
@@ -71,3 +74,4 @@ img {
 <img style="-webkit-filter: url(#displacement); filter: url(#displacement);" src="resources/reference.png">
 <img style="-webkit-filter: url(#merge); filter: url(#merge);" src="resources/reference.png">
 <img style="-webkit-filter: url(#flood); filter: url(#flood);" src="resources/reference.png">
+<img style="-webkit-filter: url(#turbulence); filter: url(#turbulence);" src="resources/reference.png">