Splitting SVG types out of dart:html.

sdk/lib/html/src/shared_SVGFactoryProviders.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of svg;
+
+final _START_TAG_REGEXP = const RegExp('<(\\w+)');
+
+class _SVGElementFactoryProvider {
+  static SVGElement createSVGElement_tag(String tag) {
+    final Element temp =
+      document.$dom_createElementNS("http://www.w3.org/2000/svg", tag);
+    return temp;
+  }
+
+  static SVGElement createSVGElement_svg(String svg) {
+    Element parentTag;
+    final match = _START_TAG_REGEXP.firstMatch(svg);
+    if (match != null && match.group(1).toLowerCase() == 'svg') {
+      parentTag = new Element.tag('div');
+    } else {
+      parentTag = new SVGSVGElement();
+    }
+
+    parentTag.innerHTML = svg;
+    if (parentTag.elements.length == 1) return parentTag.elements.removeLast();
+
+    throw new ArgumentError(
+        'SVG had ${parentTag.elements.length} '
+        'top-level elements but 1 expected');
+  }
+}
+
+class _SVGSVGElementFactoryProvider {
+  static SVGSVGElement createSVGSVGElement() {
+    final el = new SVGElement.tag("svg");
+    // The SVG spec requires the version attribute to match the spec version
+    el.attributes['version'] = "1.1";
+    return el;
+  }
+}