Core: Use QList's initializer list contructor for output panes

More concise code.

Change-Id: I0c83a02de725648294e1b6b49669bdec0c47fafe
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/autotest/testresultspane.cpp

@@ -231,8 +231,7 @@ QWidget *TestResultsPane::outputWidget(QWidget *parent)
 
 QList<QWidget *> TestResultsPane::toolBarWidgets() const
 {
-    return QList<QWidget *>() << m_expandCollapse << m_runAll << m_runSelected << m_stopTestRun
-                              << m_filterButton;
+    return { m_expandCollapse, m_runAll, m_runSelected, m_stopTestRun, m_filterButton };
 }
 
 QString TestResultsPane::displayName() const

src/plugins/coreplugin/find/searchresultwindow.cpp

@@ -340,8 +340,8 @@ QWidget *SearchResultWindow::outputWidget(QWidget *)
 */
 QList<QWidget*> SearchResultWindow::toolBarWidgets() const
 {
-    return QList<QWidget*>() << d->m_expandCollapseButton << d->m_spacer
-                             << d->m_historyLabel << d->m_spacer2 << d->m_recentSearchesBox;
+    return { d->m_expandCollapseButton, d->m_spacer,
+             d->m_historyLabel, d->m_spacer2, d->m_recentSearchesBox };
 }
 
 /*!

src/plugins/projectexplorer/appoutputpane.cpp

@@ -321,8 +321,7 @@ QWidget *AppOutputPane::outputWidget(QWidget *)
 
 QList<QWidget*> AppOutputPane::toolBarWidgets() const
 {
-    return QList<QWidget*>() << m_reRunButton << m_stopButton << m_attachButton
-                             << m_zoomInButton << m_zoomOutButton;
+    return { m_reRunButton, m_stopButton, m_attachButton, m_zoomInButton, m_zoomOutButton };
 }
 
 QString AppOutputPane::displayName() const

src/plugins/projectexplorer/compileoutputwindow.cpp

@@ -244,9 +244,7 @@ QWidget *CompileOutputWindow::outputWidget(QWidget *)
 
 QList<QWidget *> CompileOutputWindow::toolBarWidgets() const
 {
-     return QList<QWidget *>() << m_cancelBuildButton
-                               << m_zoomInButton
-                               << m_zoomOutButton;
+     return { m_cancelBuildButton, m_zoomInButton, m_zoomOutButton };
 }
 
 void CompileOutputWindow::appendText(const QString &text, BuildStep::OutputFormat format)

src/plugins/projectexplorer/taskwindow.cpp

@@ -348,7 +348,7 @@ void TaskWindow::delayedInitialization()
 
 QList<QWidget*> TaskWindow::toolBarWidgets() const
 {
-    return QList<QWidget*>() << d->m_filterWarningsButton << d->m_categoriesButton;
+    return { d->m_filterWarningsButton, d->m_categoriesButton };
 }
 
 QWidget *TaskWindow::outputWidget(QWidget *)

src/plugins/todo/todooutputpane.cpp

@@ -67,11 +67,7 @@ QWidget *TodoOutputPane::outputWidget(QWidget *parent)
 
 QList<QWidget*> TodoOutputPane::toolBarWidgets() const
 {
-    return QList<QWidget*>()
-        << m_spacer
-        << m_currentFileButton
-        << m_wholeProjectButton
-        << m_subProjectButton;
+    return { m_spacer, m_currentFileButton, m_wholeProjectButton, m_subProjectButton };
 }
 
 QString TodoOutputPane::displayName() const