Change const Regexp -> new RegExp in a few HTML files.

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+)');
+final _START_TAG_REGEXP = new 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;
@@ skipping 14 matching lines @@
 }
 
 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;
   }
 }