extends is a weird keyword in js, use extending instead

discover/qml/ApplicationsListPage.qml

@@ -36,7 +36,7 @@ DiscoverPage {
     property alias originFilter: appsModel.originFilter
     property alias mimeTypeFilter: appsModel.mimeTypeFilter
     property alias stateFilter: appsModel.stateFilter
-    property alias extend: appsModel.extends
+    property alias extending: appsModel.extending
     property alias search: appsModel.search
     property alias resourcesUrl: appsModel.resourcesUrl
     property alias isBusy: appsModel.isBusy

discover/qml/navigation.js

@@ -58,7 +58,7 @@ function openReviews(model) {
 }
 
 function openExtends(ext) {
-    window.stack.push(applicationListComp, { extend: ext, title: i18n("Extensions...") })
+    window.stack.push(applicationListComp, { extending: ext, title: i18n("Extensions...") })
 }
 
 function openHome() {

libdiscover/resources/ResourcesProxyModel.h

@@ -48,7 +48,7 @@ class DISCOVERCOMMON_EXPORT ResourcesProxyModel : public QAbstractListModel, pub
     Q_PROPERTY(QString mimeTypeFilter READ mimeTypeFilter WRITE setMimeTypeFilter)
     Q_PROPERTY(QString search READ lastSearch WRITE setSearch NOTIFY searchChanged)
     Q_PROPERTY(QUrl resourcesUrl READ resourcesUrl WRITE setResourcesUrl NOTIFY resourcesUrlChanged)
-    Q_PROPERTY(QString extends READ extends WRITE setExtends)
+    Q_PROPERTY(QString extending READ extends WRITE setExtends)
     Q_PROPERTY(bool allBackends READ allBackends WRITE setAllBackends)
     Q_PROPERTY(QVariantList subcategories READ subcategories NOTIFY subcategoriesChanged)
     Q_PROPERTY(bool isBusy READ isBusy NOTIFY busyChanged)