Fix display of a view using nuxeo-results-view

Steps to reproduce :

1. Define a page provider"mypp" in Studio with 2 predicates : ecm:parentId and dc:nature
2. configure the form and results layouts for this page provider
   1. for the form, only keep the filter on Nature
   2. for the results, add a column to display dc:nature
3. add this line to nuxeo-xxx-custom-bundle.html

   <nuxeo-slot-content name="documentCollapsiblePage" slot="DOCUMENT_VIEWS_PAGES" order="10">
     <template>
       <nuxeo-filter document="[[document]]" expression="document.facets.indexOf('Folderish') !== -1
                                                      &amp;&amp; document.type != 'Folder'">
         <template>
           <nuxeo-collapsible-document-page name="view" document="[[document]]"></nuxeo-collapsible-document-page>
         </template>
       </nuxeo-filter>
     </template>
   </nuxeo-slot-content>
   
   
   
   <nuxeo-slot-content name="myppViewPage" slot="DOCUMENT_VIEWS_PAGES">
     <template>
       <nuxeo-filter document="[[document]]" type="Folder">
         <template>
           <nuxeo-results-view show-filters provider="mypp" schemas="dublincore" search-name="mypp" params="{&quot;system_parentId&quot;:&quot;[[document.uid]]&quot;}" name="view"></nuxeo-results-view>
         </template>
       </nuxeo-filter>
     </template>
   </nuxeo-slot-content>
   

4. Deploy the Studio package and start Nuxeo
5. Create a Folder and create 2 File documents in it, with one File having dc:nature set to "Order"
6. Navigate back to the Folder
7. Observe the "0" in the Filters and this error in the console

   nuxeo-app.html-26.js:190 Uncaught TypeError: Cannot read property 'apply' of undefined
       at DomApi.proto.<computed> [as querySelector] (nuxeo-app.html-26.js:190)
       at HTMLElement._grabResults (elements.html-105.js:71)
       at HTMLElement._grabResults (elements.html-105.js:87)
       at HTMLElement._formChanged (elements.html-105.js:60)
       at HTMLElement.handler (nuxeo-app.html-12.js:79)
       at dispatchNotifyEvent (nuxeo-app.html-13.js:286)
       at Object.runNotifyEffect [as fn] (nuxeo-app.html-13.js:311)
       at runEffectsForProperty (nuxeo-app.html-13.js:142)
       at runNotifyEffects (nuxeo-app.html-13.js:229)
       at HTMLElement._propertiesChanged (nuxeo-app.html-13.js:1695)
   

8. If you try to use the filter, the Search button does not work any more