Qmljs: fix a crash when m_treeview is deleted

Change-Id: I3743815c14151b49784a20cdb0c0bba2fbde4e7b
Reviewed-by: Marco Benelli <marco.benelli@qt.io>
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/qmljseditor/qmljsoutline.cpp

@@ -125,12 +125,12 @@ void QmlJSOutlineWidget::setEditor(QmlJSEditorWidget *editor)
 
     m_filterModel->setSourceModel(m_editor->qmlJsEditorDocument()->outlineModel());
     m_treeView->expandAll();
-    connect(m_editor->qmlJsEditorDocument()->outlineModel(), &QAbstractItemModel::modelAboutToBeReset, [this]() {
-        if (m_treeView && m_treeView->selectionModel())
+    connect(m_editor->qmlJsEditorDocument()->outlineModel(), &QAbstractItemModel::modelAboutToBeReset, m_treeView, [this]() {
+        if (m_treeView->selectionModel())
             m_treeView->selectionModel()->blockSignals(true);
     });
-    connect(m_editor->qmlJsEditorDocument()->outlineModel(), &QAbstractItemModel::modelReset, [this]() {
-        if (m_treeView && m_treeView->selectionModel())
+    connect(m_editor->qmlJsEditorDocument()->outlineModel(), &QAbstractItemModel::modelReset, m_treeView, [this]() {
+        if (m_treeView->selectionModel())
             m_treeView->selectionModel()->blockSignals(false);
     });