Fix 'blocking' messageboxes not handling key focus properly

apps/openmw/mwgui/windowmanagerimp.cpp

@@ -773,6 +773,7 @@ namespace MWGui
                 double dt = frameTimer.time_s();
                 frameTimer.setStartTick();
 
+                mKeyboardNavigation->onFrame();
                 mMessageBoxManager->onFrame(dt);
                 MWBase::Environment::get().getInputManager()->update(dt, true, false);
 

files/mygui/openmw_interactive_messagebox_notransp.layout

@@ -9,6 +9,7 @@
             <Property key="WordWrap" value="true"/>
             <Property key="MultiLine" value="1"/>
             <Property key="VisibleVScroll" value="1"/>
+            <Property key="NeedKey" value="false"/>
         </Widget>
         <Widget type="Widget" skin="" position="0 0 500 400" align="Stretch" name="buttons">
         </Widget>