[FIX] web_editor: save all child text nodes of oe_structure elements

When saving the content of an oe_structure, the starting text nodes
were lost because only the internal *elements* were considered. Ending
text nodes were kept since they are considered as the last element's
tail by the etree library.

task-2040764

closes odoo/odoo#43375

X-original-commit: eb71d25ce965ecdb20c26517627aed5b43f8b990
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/web_editor/models/ir_ui_view.py

@@ -67,6 +67,7 @@ class IrUiView(models.Model):
         xpath = etree.Element('xpath', expr="//*[hasclass('oe_structure')][@id='{}']".format(el.get('id')), position="replace")
         arch.append(xpath)
         structure = etree.Element(el.tag, attrib=el.attrib)
+        structure.text = el.text
         xpath.append(structure)
         for child in el.iterchildren(tag=etree.Element):
             structure.append(copy.deepcopy(child))