overlay: Disable fading marquee for a small speedup

Before: http://winsuk.net/screens/liberty/withfadingmarquee.png
After: http://winsuk.net/screens/liberty/withoutfadingmarquee.png

See "Enable Bluetooth HCI snoo-" in screenshots for what this change looks like

Change-Id: I173e3df8f2a7a50a3e914a9cdd0ca9f57de41c47