QmlDesigner: Consolidate context help

Move one singular implementation to the texteditor.
Define a fallback help URL if no type is found.

Change-Id: Ieccbeb449c22ff14060d1fb57dfd629770baf6f1
Reviewed-by: Henning Gründl <henning.gruendl@qt.io>

src/plugins/qmldesigner/components/navigator/navigatorwidget.cpp

@@ -181,23 +181,7 @@ QToolBar *NavigatorWidget::createToolBar()
 void NavigatorWidget::contextHelp(const Core::IContext::HelpCallback &callback) const
 {
     if (auto view = navigatorView()) {
-        QmlDesignerPlugin::emitUsageStatistics(Constants::EVENT_HELP_REQUESTED
-                                               + view->contextHelpId());
-#ifndef QDS_USE_PROJECTSTORAGE
-        ModelNode selectedNode = view->firstSelectedModelNode();
-        if (!selectedNode)
-            selectedNode = view->rootModelNode();
-
-        // TODO: Needs to be fixed for projectstorage.
-        const Core::HelpItem helpItem({QString::fromUtf8("QML." + selectedNode.type()),
-                                       "QML." + selectedNode.simplifiedTypeName()},
-                                      {},
-                                      {},
-                                      Core::HelpItem::QmlComponent);
-        callback(helpItem);
-#else
         QmlDesignerPlugin::contextHelp(callback, view->contextHelpId());
-#endif
     } else {
         callback({});
     }

src/plugins/qmldesigner/components/texteditor/texteditorview.cpp

@@ -142,10 +142,30 @@ WidgetInfo TextEditorView::widgetInfo()
 
 void TextEditorView::qmlJSEditorContextHelp(const Core::IContext::HelpCallback &callback) const
 {
+#ifndef QDS_USE_PROJECTSTORAGE
+    ModelNode selectedNode = firstSelectedModelNode();
+    if (!selectedNode)
+        selectedNode = rootModelNode();
+
+    // TODO: Needs to be fixed for projectstorage.
+    Core::HelpItem helpItem({QString::fromUtf8("QML." + selectedNode.type()),
+                             "QML." + selectedNode.simplifiedTypeName()},
+                            {},
+                            {},
+                            Core::HelpItem::QmlComponent);
+
+    if (!helpItem.isValid()) {
+        helpItem = Core::HelpItem(
+            QUrl("qthelp://org.qt-project.qtdesignstudio/doc/quick-preset-components.html"));
+    }
+
+    callback(helpItem);
+#else
     if (m_widget->textEditor())
         m_widget->textEditor()->contextHelp(callback);
     else
         callback({});
+#endif
 }
 
 void TextEditorView::nodeIdChanged(const ModelNode& /*node*/, const QString &/*newId*/, const QString &/*oldId*/)