textArea with incremental text child does not work

[haraldsteinlechner]

...

[krauthaufen]

texts are currently shown using span nodes...
The main problem here is that the text needs to be 'identifyable' in the output, so the span gets an id and is known to have only text content.

Maybe we should simply inline text in its parent whenever possible. This can only be done when the parent only has a single text child (statically). The only way to do that is via checking IsConstant on the parent's child-list and requires relatively sophisticated tweaks in the update code...