Unclear docs: v3-v4 migration of horizontal forms, .col-form-label vs. .form-control-label

Created by: Herst

The example code for a horizontal form in v3:

<form class="form-horizontal">
  <div class="form-group">
    <label for="inputEmail3" class="col-sm-2 control-label">Email</label>
    <div class="col-sm-10">
      <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
    </div>
  </div>
  […]
</form>

Let's say we wanted to port it to v4. The relevant parts from the migration document:

Renamed .control-label to .form-control-label. […]

Horizontal forms overhauled:

Dropped the .form-horizontal class requirement.

.form-group no longer applies styles from the .row via mixin, so .row is now required for horizontal grid layouts (e.g., <div class="form-group row">).

Added new .form-control-label class to vertically center labels with .form-controls.

Added new .form-row for compact form layouts with the grid classes (swap your .row for a .form-row and go).

(Highlight by me.)

OK, so the code would turn into:

<form>
  <div class="form-group row">
    <label for="inputEmail3" class="col-sm-2 form-control-label">Email</label>
    <div class="col-sm-10">
      <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
    </div>
  </div>
  […]
</form>

But if we were to look at the v4 example code for horizontal forms we see that it's different:

<div class="container">
  <form>
    <div class="form-group row">
      <label for="inputEmail3" class="col-sm-2 col-form-label">Email</label>
      <div class="col-sm-10">
        <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
      </div>
    </div>
    […]
  </form>
</div>

There are two discrepancies:

.container around it, I think this one can be ignored, it's obvious that it's just for style.
.col-form-label for the label instead of .form-control-label. Former is never mentioned in the migration doc and latter is not mentioned in the forms documentation, so what is it now?