widget as a std::unique_ptr is bad

- a widget is often used as a raw pointer and in most cases
   the parent will take care of destructing it
 - here the context is also destructing the widget
 - so move back to QPointer and keep deleting to the context

Change-Id: Ief5c4faa08d5e76f723b35d33d09fafc502c2d8a
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

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

@@ -66,7 +66,7 @@ const char TEXTEDITOR_CONTEXT_ID[] = "QmlDesigner.TextEditorContext";
 TextEditorView::TextEditorView(QObject *parent)
     : AbstractView(parent)
     , m_widget(new TextEditorWidget(this))
-    , m_textEditorContext(new Internal::TextEditorContext(m_widget.get()))
+    , m_textEditorContext(new Internal::TextEditorContext(m_widget))
 {
     Core::ICore::addContextObject(m_textEditorContext);
 
@@ -89,6 +89,7 @@ TextEditorView::TextEditorView(QObject *parent)
 
 TextEditorView::~TextEditorView()
 {
+    // m_textEditorContext is responsible for deleting the widget
 }
 
 void TextEditorView::modelAttached(Model *model)
@@ -148,7 +149,7 @@ void TextEditorView::nodeReparented(const ModelNode &/*node*/, const NodeAbstrac
 
 WidgetInfo TextEditorView::widgetInfo()
 {
-    return createWidgetInfo(m_widget.get(), 0, "TextEditor", WidgetInfo::CentralPane, 0, tr("Text Editor"), DesignerWidgetFlags::IgnoreErrors);
+    return createWidgetInfo(m_widget, 0, "TextEditor", WidgetInfo::CentralPane, 0, tr("Text Editor"), DesignerWidgetFlags::IgnoreErrors);
 }
 
 void TextEditorView::contextHelpId(const Core::IContext::HelpIdCallback &callback) const

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

@@ -101,7 +101,7 @@ public:
     void reformatFile();
 
 private:
-    std::unique_ptr<TextEditorWidget> m_widget;
+    QPointer<TextEditorWidget> m_widget;
     Internal::TextEditorContext *m_textEditorContext;
 };