68cb239bb0
view.getRootView returns itself when unattached, which may not be a ViewGroup instance. Therefore trying to cast to a ViewGroup will cause a ClassCastException. This fix avoids the exception by ensuring that the view is attached before trying to cast the root view. Fixes: 277637573 Test: mp droid and verified touch gestures on dream work correctly by swiping up the bouncer, and swiping down the notification shade. Change-Id: Ic2d87278e5c60509c39062437b548ae76959b169