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

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

Index: client/dom/generated/src/frog/SVGFEOffsetElement.dart
diff --git a/client/dom/generated/src/frog/SVGFEOffsetElement.dart b/client/dom/generated/src/frog/SVGFEOffsetElement.dart
index 2b9bb1b2dad6fbabc20950aac33eeb297034fcc8..17d3258e1f4ea5cfdee72791805b3a378c647f37 100644
--- a/client/dom/generated/src/frog/SVGFEOffsetElement.dart
+++ b/client/dom/generated/src/frog/SVGFEOffsetElement.dart
@@ -1,29 +1,29 @@
 
 class _SVGFEOffsetElementJs extends _SVGElementJs implements SVGFEOffsetElement native "*SVGFEOffsetElement" {
 
-  _SVGAnimatedNumberJs get dx() native "return this.dx;";
+  final _SVGAnimatedNumberJs dx;
 
-  _SVGAnimatedNumberJs get dy() native "return this.dy;";
+  final _SVGAnimatedNumberJs dy;
 
-  _SVGAnimatedStringJs get in1() native "return this.in1;";
+  final _SVGAnimatedStringJs in1;
 
   // From SVGFilterPrimitiveStandardAttributes
 
-  _SVGAnimatedLengthJs get height() native "return this.height;";
+  final _SVGAnimatedLengthJs height;
 
-  _SVGAnimatedStringJs get result() native "return this.result;";
+  final _SVGAnimatedStringJs result;
 
-  _SVGAnimatedLengthJs get width() native "return this.width;";
+  final _SVGAnimatedLengthJs width;
 
-  _SVGAnimatedLengthJs get x() native "return this.x;";
+  final _SVGAnimatedLengthJs x;
 
-  _SVGAnimatedLengthJs get y() native "return this.y;";
+  final _SVGAnimatedLengthJs y;
 
   // 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;
 }