Core: Simplify MainWindow::init() signature

And adapt its only user.

Change-Id: Ifc1f6c7857951d6e1a68f5bc909146e9689c5428
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/coreplugin/coreplugin.cpp

@@ -144,12 +144,10 @@ bool CorePlugin::initialize(const QStringList &arguments, QString *errorMessage)
         m_mainWindow->setOverrideColor(args.overrideColor);
     m_locator = new Locator;
     qsrand(QDateTime::currentDateTime().toTime_t());
-    const bool success = m_mainWindow->init(errorMessage);
-    if (success) {
+    m_mainWindow->init();
     m_editMode = new EditMode;
     ModeManager::activateMode(m_editMode->id());
     InfoBar::initialize(ICore::settings(), creatorTheme());
-    }
 
     IWizardFactory::initialize();
 
@@ -204,7 +202,7 @@ bool CorePlugin::initialize(const QStringList &arguments, QString *errorMessage)
 
     Utils::PathChooser::setAboutToShowContextMenuHandler(&CorePlugin::addToPathChooserContextMenu);
 
-    return success;
+    return true;
 }
 
 void CorePlugin::extensionsInitialized()

src/plugins/coreplugin/mainwindow.cpp

@@ -288,13 +288,10 @@ MainWindow::~MainWindow()
     m_jsExpander = nullptr;
 }
 
-bool MainWindow::init(QString *errorMessage)
+void MainWindow::init()
 {
-    Q_UNUSED(errorMessage)
-
     m_progressManager->init(); // needs the status bar manager
     MessageManager::init();
-    return true;
 }
 
 void MainWindow::extensionsInitialized()

src/plugins/coreplugin/mainwindow.h

@@ -78,7 +78,7 @@ public:
     MainWindow();
     ~MainWindow();
 
-    bool init(QString *errorMessage);
+    void init();
     void extensionsInitialized();
     void aboutToShutdown();