Use fields in hidden native DOM classes instead of getters/setters.

client/dom/generated/src/frog/SVGDescElement.dart

Index: client/dom/generated/src/frog/SVGDescElement.dart
diff --git a/client/dom/generated/src/frog/SVGDescElement.dart b/client/dom/generated/src/frog/SVGDescElement.dart
index c99e284808f32a536fea32c93eef507095c2b6e6..ea07714f5a135e79322a5cfad235dcdb35c64ca2 100644
--- a/client/dom/generated/src/frog/SVGDescElement.dart
+++ b/client/dom/generated/src/frog/SVGDescElement.dart
@@ -3,19 +3,15 @@ class _SVGDescElementJs extends _SVGElementJs implements SVGDescElement native "
 
   // From SVGLangSpace
 
-  String get xmllang() native "return this.xmllang;";
+  String xmllang;
 
-  void set xmllang(String value) native "this.xmllang = value;";
-
-  String get xmlspace() native "return this.xmlspace;";
-
-  void set xmlspace(String value) native "this.xmlspace = value;";
+  String xmlspace;
 
   // From SVGStylable
 
-  _SVGAnimatedStringJs get className() native "return this.className;";
+  final _SVGAnimatedStringJs className;
 
-  _CSSStyleDeclarationJs get style() native "return this.style;";
+  final _CSSStyleDeclarationJs style;
 
   _CSSValueJs getPresentationAttribute(String name) native;
 }