Fix #5085 and #5152

- In the pause menu, the buttons are part of ribbon widgets. Under certain conditions, the game could incorrectly select the underlying back button as active instead of its ribbon. Because the icon buttons that constitute a ribbon widget don't have their x or y property set, a check that x or y are not negative ensures that keyboard navigation doesn't select them.
- The multiplayer focus dispatcher button is made invisible if there is only one player in the kart selection screen.
- Add a getName() function to the Widget class, to help when debugging GUI.

src/guiengine/event_handler.cpp

@@ -540,10 +540,12 @@ int EventHandler::findIDClosestWidget(const NavigationDirection nav, const int p
         // - it corresponds to the current widget
         // - it corresponds to an invisible or disabled widget
         // - the player is not allowed to select it
+        // - Its base coordinates are negative (such as buttons within ribbons)
         if (w_test == NULL || !Widget::isFocusableId(i) || w == w_test ||
             (!w_test->isVisible()   && ignore_disabled) ||
             (!w_test->isActivated() && ignore_disabled) ||
-            (playerID != PLAYER_ID_GAME_MASTER && !w_test->m_supports_multiplayer))
+            (playerID != PLAYER_ID_GAME_MASTER && !w_test->m_supports_multiplayer) ||
+            (w_test->m_x < 0) || (w_test->m_y < 0))
             continue;
 
         // Ignore empty ribbon widgets and lists

src/guiengine/widget.hpp

@@ -520,6 +520,10 @@ namespace GUIEngine
           */
         int getID() const { return m_id; }
 
+        /** Get the name used for this widget in the GUI files or set in the code
+         * Use only for debugging. */
+        std::string getName() { return m_properties[PROP_ID]; }
+
         /** Get whether this object is allowed to receive focus */
         bool isFocusable() const { return m_focusable; }
 

src/states_screens/kart_selection.cpp

@@ -148,9 +148,7 @@ EventPropagation FocusDispatcher::focused(const int player_id)
             //             ->getIrrlichtElement()->getID() <<
             //             ")" << std::endl;
 
-            m_parent->m_kart_widgets[n].m_player_ident_spinner
-            ->setFocusForPlayer(player_id);
-
+            m_parent->m_kart_widgets[n].m_player_ident_spinner->setFocusForPlayer(player_id);
 
             return GUIEngine::EVENT_BLOCK;
         }
@@ -438,6 +436,8 @@ void KartSelectionScreen::init()
                 // if kart from config not found, select the first instead
                 w->setSelection(0, 0, true);
             }
+
+            m_dispatcher->setVisible(false);
         }
         else
         {