QmlDesigner: Avoid leaking unused view widgets

IF a widget is never shown it has no parent
and has to be deleted manually.

Change-Id: I5cf34e3a7706dd3472d4388a04bf12910530fe4d
Reviewed-by: Tim Jenssen <tim.jenssen@theqtcompany.com>

src/plugins/qmldesigner/designmodewidget.cpp

@@ -192,6 +192,13 @@ DesignModeWidget::DesignModeWidget(QWidget *parent) :
 
 DesignModeWidget::~DesignModeWidget()
 {
+    m_leftSideBar.reset();
+    m_rightSideBar.reset();
+
+    foreach (QPointer<QWidget> widget, m_viewWidgets) {
+        if (widget)
+            widget.clear();
+    }
 }
 
 void DesignModeWidget::restoreDefaultView()
@@ -382,7 +389,9 @@ void DesignModeWidget::setup()
             Core::SideBarItem *sideBarItem = new DesignerSideBarItem(widgetInfo.widget, widgetInfo.toolBarWidgetFactory, widgetInfo.uniqueId);
             sideBarItems.append(sideBarItem);
             rightSideBarItems.append(sideBarItem);
+
         }
+        m_viewWidgets.append(widgetInfo.widget);
     }
 
     if (projectsExplorer) {

src/plugins/qmldesigner/designmodewidget.h

@@ -160,6 +160,8 @@ private: // variables
     QStringList m_navigatorHistory;
     int m_navigatorHistoryCounter;
     bool m_keepNavigatorHistory;
+
+    QList<QPointer<QWidget> >m_viewWidgets;
 };
 
 } // namespace Internal