MainWindow (macOS): Defeat Qt's menu text heuristic

Workaround for QTBUG-30812. Resolves #1067.

Author: dg0yt

src/gui/main_window.cpp

@@ -1,6 +1,6 @@
 /*
  *    Copyright 2012, 2013, 2014 Thomas Schöps
- *    Copyright 2012-2017 Kai Pastor
+ *    Copyright 2012-2018 Kai Pastor
  *
  *    This file is part of OpenOrienteering.
  *
@@ -255,6 +255,26 @@ void MainWindow::setController(MainWindowController* new_controller, bool has_fi
 		createHelpMenu();
 
 #if defined(Q_OS_MACOS)
+	// Defeat Qt's menu text heuristic, as a workaround for QTBUG-30812.
+	// Changing an action's menu role (to QAction::NoRole) after it was
+	// added to the menu is unsupported and triggers crashes (#1077).
+	// Instead, we defeat the heuristic by adding a zero width space at the
+	// beginning and the end of the text of every action in the menus.
+	const auto menubar_actions = menuBar()->actions();
+	for (auto action : menubar_actions)
+	{
+		if (const auto menu = action->menu())
+		{
+			const auto menu_actions = menu->actions();
+			for (auto action : menu_actions)
+			{
+				static const auto zwsp = QString::fromUtf8("\u200B");
+				action->setText(zwsp + action->text() + zwsp);
+			}
+		}
+	}
+
+	// Needed to activate the menu bar changes
 	if (isVisible() && qApp->activeWindow() == this)
 	{
 		// Force a menu synchronisation,

src/gui/map/map_editor.cpp

@@ -871,9 +871,6 @@ void MapEditorController::createActions()
 
 	show_grid_act = newCheckAction("showgrid", tr("Show grid"), this, SLOT(showGrid()), "grid.png", QString{}, "grid.html");
 	configure_grid_act = newAction("configuregrid", tr("Configure grid..."), this, SLOT(configureGrid()), "grid.png", QString{}, "grid.html");
-#if defined(Q_OS_MACOS)
-	configure_grid_act->setMenuRole(QAction::NoRole);
-#endif
 	pan_act = newToolAction("panmap", tr("Pan"), this, SLOT(pan()), "move.png", QString{}, "view_menu.html");
 	move_to_gps_pos_act = newAction("movegps", tr("Move to my location"), this, SLOT(moveToGpsPos()), "move-to-gps.png", QString{}, "view_menu.html");
 	move_to_gps_pos_act->setEnabled(false);