Change highlight text colours in OSX sys settings.

wxSYS_COLOUR_LISTBOXHIGHLIGHTTEXT is usually used on a darker background provided by wxRender::DrawItemSelectionRect so a light color makes sense. While wxSYS_COLOUR_HIGHLIGHTTEXT is used on a lighter blue shade where the dark color makes sense.

src/osx/cocoa/settings.mm

@@ -88,9 +88,11 @@ wxColour wxSystemSettingsNative::GetColour(wxSystemColour index)
         sysColor = [NSColor controlHighlightColor];
         break;
     case wxSYS_COLOUR_HIGHLIGHTTEXT:
-    case wxSYS_COLOUR_LISTBOXHIGHLIGHTTEXT:
         sysColor = [NSColor selectedTextColor];
         break;
+    case wxSYS_COLOUR_LISTBOXHIGHLIGHTTEXT:
+        sysColor = [NSColor alternateSelectedControlTextColor];
+        break;
     case wxSYS_COLOUR_INFOBK:
         // tooltip (bogus)
         sysColor = [NSColor windowBackgroundColor];