[erp5_web_renderjs_ui] LabelField should not write in subgadget span

Regression introduced by nexedi/erp5@cf1a0610

bt5/erp5_web_renderjs_ui/PathTemplateItem/web_page_module/rjs_gadget_erp5_label_field_js.js

@@ -124,15 +124,21 @@
 
       if (modification_dict.hasOwnProperty('error_text')) {
         // first remove old errors
-        span = this.state.container_element.querySelector('span');
-        if (span) {
-          this.state.container_element.removeChild(span);
+        span = this.state.container_element.lastElementChild;
+        if ((span !== null) && (span.tagName.toLowerCase() !== 'span')) {
+          span = null;
         }
         // display new error if present
         if (this.state.error_text) {
+          if (span === null) {
             span = document.createElement('span');
             span.textContent = this.state.error_text;
             this.state.container_element.appendChild(span);
+          } else {
+            span.textContent = this.state.error_text;
+          }
+        } else if (span !== null) {
+          this.state.container_element.removeChild(span);
         }
       }
 

bt5/erp5_web_renderjs_ui/PathTemplateItem/web_page_module/rjs_gadget_erp5_label_field_js.xml

@@ -230,7 +230,7 @@
             </item>
             <item>
                 <key> <string>serial</string> </key>
-                <value> <string>961.46539.43459.6519</string> </value>
+                <value> <string>964.7149.35202.27306</string> </value>
             </item>
             <item>
                 <key> <string>state</string> </key>
@@ -248,7 +248,7 @@
                     </tuple>
                     <state>
                       <tuple>
-                        <float>1503932157.58</float>
+                        <float>1513181723.22</float>
                         <string>UTC</string>
                       </tuple>
                     </state>