gtk3: replace old action if same command is added

i.e. originally we preferred the old action, now
prefer the new action because e.g. wrap items in
writer only contain their "checkable" state on
their update

Change-Id: I6a6ce94126253396cc273834a7e8a4fb0a56921d

vcl/unx/gtk/gtksalmenu.cxx

@@ -530,30 +530,31 @@ void GtkSalMenu::NativeSetItemCommand( unsigned nSection,
 
     GVariant *pTarget = nullptr;
 
-    if ( g_action_group_has_action( mpActionGroup, aCommand ) == FALSE ) {
-        if ( ( nBits & MenuItemBits::CHECKABLE ) || bIsSubmenu )
-        {
-            // Item is a checkmark button.
-            GVariantType* pStateType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_BOOLEAN) );
-            GVariant* pState = g_variant_new_boolean( bChecked );
+    if (g_action_group_has_action(mpActionGroup, aCommand))
+        g_lo_action_group_remove(pActionGroup, aCommand);
 
-            g_lo_action_group_insert_stateful( pActionGroup, aCommand, nId, bIsSubmenu, nullptr, pStateType, nullptr, pState );
-        }
-        else if ( nBits & MenuItemBits::RADIOCHECK )
-        {
-            // Item is a radio button.
-            GVariantType* pParameterType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_STRING) );
-            GVariantType* pStateType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_STRING) );
-            GVariant* pState = g_variant_new_string( "" );
-            pTarget = g_variant_new_string( aCommand );
+    if ( ( nBits & MenuItemBits::CHECKABLE ) || bIsSubmenu )
+    {
+        // Item is a checkmark button.
+        GVariantType* pStateType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_BOOLEAN) );
+        GVariant* pState = g_variant_new_boolean( bChecked );
 
-            g_lo_action_group_insert_stateful( pActionGroup, aCommand, nId, FALSE, pParameterType, pStateType, nullptr, pState );
-        }
-        else
-        {
-            // Item is not special, so insert a stateless action.
-            g_lo_action_group_insert( pActionGroup, aCommand, nId, FALSE );
-        }
+        g_lo_action_group_insert_stateful( pActionGroup, aCommand, nId, bIsSubmenu, nullptr, pStateType, nullptr, pState );
+    }
+    else if ( nBits & MenuItemBits::RADIOCHECK )
+    {
+        // Item is a radio button.
+        GVariantType* pParameterType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_STRING) );
+        GVariantType* pStateType = g_variant_type_new( reinterpret_cast<gchar const *>(G_VARIANT_TYPE_STRING) );
+        GVariant* pState = g_variant_new_string( "" );
+        pTarget = g_variant_new_string( aCommand );
+
+        g_lo_action_group_insert_stateful( pActionGroup, aCommand, nId, FALSE, pParameterType, pStateType, nullptr, pState );
+    }
+    else
+    {
+        // Item is not special, so insert a stateless action.
+        g_lo_action_group_insert( pActionGroup, aCommand, nId, FALSE );
     }
 
     GLOMenu* pMenu = G_LO_MENU( mpMenuModel );