Add dummy dart:html library for documentation.

lib/html/doc/interface/SVGFEDiffuseLightingElement.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.
+
+// WARNING: Do not edit - generated code.
+
+/// @domName SVGFEDiffuseLightingElement
+interface SVGFEDiffuseLightingElement extends SVGElement, SVGFilterPrimitiveStandardAttributes {
+
+  /** @domName SVGFEDiffuseLightingElement.diffuseConstant */
+  final SVGAnimatedNumber diffuseConstant;
+
+  /** @domName SVGFEDiffuseLightingElement.in1 */
+  final SVGAnimatedString in1;
+
+  /** @domName SVGFEDiffuseLightingElement.kernelUnitLengthX */
+  final SVGAnimatedNumber kernelUnitLengthX;
+
+  /** @domName SVGFEDiffuseLightingElement.kernelUnitLengthY */
+  final SVGAnimatedNumber kernelUnitLengthY;
+
+  /** @domName SVGFEDiffuseLightingElement.surfaceScale */
+  final SVGAnimatedNumber surfaceScale;
+}