This PR is based on #12917, please review that one first.

As suggested in #12905, this PR places private methods before private static properties, see also the commit message for the rationale.

Per 15.7.12 Runtime Semantics: ClassDefinitionEvaluation, when DefineField is invoked, the class binding used in field initializer will have a receiver F, which has all static methods defined but may still have uninvoked initializer due to the order of DefineField executions on staticFields. Therefore, we place static class methods definition before static field.

For example, the following snippet

class C {
  static #p = 1;
  static get #m() {}
}

"use strict";

class C {}

var _get_m = function () {};

var _p = {
  writable: true,
  value: 1
};
var _m = {
  get: _get_m,
  set: void 0
};
new C();

"use strict";

class C {}

var _get_m = function () {};

var _m = {
  get: _get_m,
  set: void 0
};
var _p = {
  writable: true,
  value: 1
};
new C();

where _m is placed before _p, so when _p.value is evaluated, the static method descriptor _m will have been defined.