40 columns                              |
>>> long parameters list, this.field
class Foo {
  Foo(this.first, this.second, this.third, this.fourth);
}
<<<
class Foo {
  Foo(this.first, this.second,
      this.third, this.fourth);
}
>>> indent parameters more if body is a wrapped =>
method(int firstArgument, int argumentTwo) => "very long body that must wrap";
<<<
method(int firstArgument,
        int argumentTwo) =>
    "very long body that must wrap";