Rename the current Label component to NativeLabel and create a new Label that is compatible with FW8 Label

Currently the Label component creates a <label> element in the client, which makes it not suitable to rendering loose text in the page, since the <label> in meant to be used in conjunction with other elements (usually <input>). This makes it semantically different from the old Label in FW8, which creates a <div> instead.

On top of that, the <label> element is an interactive content element, which makes it behave differently than a regular text in the page. For example, when used inside a Grid cell, clicking on a label doesn’t trigger the selection of the row (see https://github.com/vaadin/flow/issues/4313 for details).

My proposal to this issue is the following:

1. Rename the current class from Label to NativeLabel (using the same naming structure as the NativeButton);
2. Create a new Label class that behaves exactly like the old Label from FW8;
3. Update demos and starters to use the new Label class;
4. Update the documentation explaining the difference between those two classes.

[heruan]

I wouldn’t rename Label. New developers approaching Vaadin will likely expect Label to be <label>, as Div is <div> and H1 is <h1>, and FW8 users are being made well aware that many things changed in Flow to be more HTML-intuitive.

I’d see more fit just a note in the Label JavaDoc warning about this.

[pleku]

I see no reason to do any drastic changes anymore for this - yes it is something that existing (or swing based) users run into, but there has not really been that much questions and uproar on this topic that would make us want to change things anymore.

So I’m quite close to closing this as won’t fix.