ExtensionManager: Streamline mode widget setup a bit

Change-Id: Ic6ec02c07cd37ee2a3b3b2d45b9239b22873a6cb
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/extensionmanager/extensionmanagerplugin.cpp

@@ -20,11 +20,6 @@
 #include <extensionsystem/iplugin.h>
 
 #include <utils/icon.h>
-#include <utils/layoutbuilder.h>
-#include <utils/styledbar.h>
-
-#include <QAction>
-#include <QMainWindow>
 
 using namespace Core;
 using namespace Utils;
@@ -46,18 +41,8 @@ public:
                                  Theme::IconsModeWelcomeActiveColor}});
         setIcon(Icon::modeIcon(FLAT, FLAT, FLAT_ACTIVE));
         setPriority(72);
-
-        using namespace Layouting;
-        auto widget = Column {
-            new StyledBar,
-            createExtensionManagerWidget(),
-            noMargin, spacing(0),
-        }.emerge();
-
-        setWidget(widget);
+        setWidgetCreator(&createExtensionManagerWidget);
     }
-
-    ~ExtensionManagerMode() { delete widget(); }
 };
 
 class ExtensionManagerPlugin final : public ExtensionSystem::IPlugin

src/plugins/extensionmanager/extensionmanagerwidget.cpp

@@ -29,6 +29,7 @@
 #include <utils/infolabel.h>
 #include <utils/layoutbuilder.h>
 #include <utils/networkaccessmanager.h>
+#include <utils/styledbar.h>
 #include <utils/stylehelper.h>
 #include <utils/temporarydirectory.h>
 #include <utils/utilsicons.h>
@@ -495,10 +496,14 @@ ExtensionManagerWidget::ExtensionManagerWidget()
         noMargin, spacing(0),
     }.attachTo(descriptionColumns);
 
-    Row {
-        Space(SpacingTokens::ExVPaddingGapXl),
-        m_extensionBrowser,
-        descriptionColumns,
+    Column {
+        new StyledBar,
+        Row {
+            Space(SpacingTokens::ExVPaddingGapXl),
+            m_extensionBrowser,
+            descriptionColumns,
+            noMargin, spacing(0),
+        },
         noMargin, spacing(0),
     }.attachTo(this);