For the following reduced test-case the order in how the dynamic nodes
in the item tree were generated (and dyn indices assigned) differed from
the way the visit_dynamic_children slots were generated:
```
Blah := Rectangle {
for x in 1: Text {
text: "Should be on the right";
}
}
MainWindow := Window {
width: 772px;
height: 504px;
Text {
if (false): TouchArea {
}
}
Blah {
x: 200px;
}
}
```
The item tree node was constructed using build_item_tree, which
basically assigned dyn index 0 to the "repater" for the touch area
and "1" to the one for the repeater inside the sub-component.
Afterwards we traversed the element tree - without descending into the
sub-components - to generate the fields and the dispatch in in the
dynamic visitor. Here a subtle order would result in a mismatch of
indices:
recurse_elem_level_order would end up visiting Text, Blah and then
Text's children, assigning the first dynamic index to Blah.
This is now fixed by merging the two iterations into one.
