Initial scroll-blocks-on compositor integration

Source/core/css/svg.css

 /*
  * The default style sheet used to render SVG.
  *
  * Copyright (C) 2005, 2006 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 31 matching lines @@
     Opera/Firefox & WebKit agreed on NOT setting "overflow: hidden" for the outermost svg element - SVG 1.1 Errata
     contains these changes as well as all future SVG specifications: see http://lists.w3.org/Archives/Public/public-svg-wg/2008JulSep/0347.html
 */
 
 svg:not(:root), symbol, image, marker, pattern, foreignObject {
     overflow: hidden
 }
 
 svg:root {
     width: 100%;
-    height: 100%
+    height: 100%;
+    scroll-blocks-on: start-touch wheel-event;
 }
 
 text, foreignObject {
     display: block
 }
 
 text {
    white-space: nowrap
 }
 
 tspan, textPath {
    white-space: inherit
 }
 
 /* states */
 
 :focus {
     outline: auto 5px -webkit-focus-ring-color
 }
 
 /* CSS transform specification: "transform-origin 0 0 for SVG elements without associated CSS layout box, 50% 50% for all other elements". */
  
 * {
     -webkit-transform-origin: 0 0;
 }
 
 html|* > svg {
     -webkit-transform-origin: 50% 50%;
 }