Fix a BadTokenException when user wakeuped device
Fix a BadTokenException when user wakeuped device

SlideshowActivity will be destoryed if user pressed POWER
to sleep the device, since it was set to noHistory=true in
AndroidManifest.xml. So it will make SlideView throw a
BadTokenException when user wakeup and then scroll the
SlideView.

Change-Id: Ib67e7547aa47f7c7c6bb469c07482f24db34668d
Signed-off-by: Roger Chen <978f296cd7dd9dd5e3d0b6fa935716127e021333@gmail.com>

bmaupin/android-sms-plus