[IMP] ir.qweb: avoid repeatedly searching the registry for nonexistant widget models

openerp/addons/base/ir/ir_qweb.py

@@ -353,7 +353,7 @@ class QWeb(orm.AbstractModel):
 
     def render_tag_esc(self, element, template_attributes, generated_attributes, qwebcontext):
         options = json.loads(template_attributes.get('esc-options') or '{}')
-        widget = self.get_widget_for(options.get('widget', ''))
+        widget = self.get_widget_for(options.get('widget'))
         inner = widget.format(template_attributes['esc'], options, qwebcontext)
         return self.render_element(element, template_attributes, generated_attributes, qwebcontext, inner)
 
@@ -462,7 +462,8 @@ class QWeb(orm.AbstractModel):
         return self.pool.get('ir.qweb.field.' + field_type, self.pool['ir.qweb.field'])
 
     def get_widget_for(self, widget):
-        return self.pool.get('ir.qweb.widget.' + widget, self.pool['ir.qweb.widget'])
+        widget_model = ('ir.qweb.widget.' + widget) if widget else 'ir.qweb.widget'
+        return self.pool.get(widget_model) or self.pool['ir.qweb.widget']
 
     def get_attr_bool(self, attr, default=False):
         if attr: