crashtesting: old files using StartWithNavigator fail to load

regression from...

commit 2503a1e9
Date:   Wed Jan 27 12:19:28 2016 -0500

    tdf#96414 Remove showing navigator during slideshow

    This isn't very user-friendly and the presenter console
    does a much better job of this.

Change-Id: I10bec1bcd2305524446a20a34494c265330e4c10

sd/source/ui/slideshow/slideshow.cxx

@@ -116,6 +116,7 @@ const SfxItemPropertyMapEntry* ImplGetPresentationPropertyMap()
         { OUString("IsShowLogo"),               ATTR_PRESENT_SHOW_PAUSELOGO,    cppu::UnoType<bool>::get(),                0, 0 },
         { OUString("IsTransitionOnClick"),      ATTR_PRESENT_CHANGE_PAGE,       cppu::UnoType<bool>::get(),                0, 0 },
         { OUString("Pause"),                    ATTR_PRESENT_PAUSE_TIMEOUT,     ::cppu::UnoType<sal_Int32>::get(),    0, 0 },
+        { OUString("StartWithNavigator"),       ATTR_PRESENT_NAVIGATOR,         cppu::UnoType<bool>::get(),                0, 0 },
         { OUString("UsePen"),                   ATTR_PRESENT_PEN,               cppu::UnoType<bool>::get(),                0, 0 },
         { OUString(), 0, css::uno::Type(), 0, 0 }
     };
@@ -439,6 +440,10 @@ void SAL_CALL SlideShow::setPropertyValue( const OUString& aPropertyName, const
         }
         break;
     }
+    case ATTR_PRESENT_NAVIGATOR:
+        bIllegalArgument = false;
+        //ignored, but exists in some older documents
+        break;
     case ATTR_PRESENT_PEN:
     {
         bool bVal = false;
@@ -561,6 +566,8 @@ Any SAL_CALL SlideShow::getPropertyValue( const OUString& PropertyName ) throw(U
         return Any( rPresSettings.mbMouseVisible );
     case ATTR_PRESENT_ALWAYS_ON_TOP:
         return Any( rPresSettings.mbAlwaysOnTop );
+    case ATTR_PRESENT_NAVIGATOR:
+        return Any( sal_False );
     case ATTR_PRESENT_PEN:
         return Any( rPresSettings.mbMouseAsPen );
     case ATTR_PRESENT_PAUSE_TIMEOUT: