Move frog dart:dom from fields to getters/setters.

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

 
 class SVGPathSegMovetoRel extends SVGPathSeg native "*SVGPathSegMovetoRel" {
 
-  num x;
+  num get x() native "return this.x;";
 
-  num y;
+  void set x(num value) native "this.x = value;";
+
+  num get y() native "return this.y;";
+
+  void set y(num value) native "this.y = value;";
 }