Fix NPE if pulling down QS quickly on very first boot.

The cling interception code can interfere with the touch
stream to the point that PanelView might get an ACTION_UP or
_CANCEL without a corresponding ACTION_DOWN, causing
problems.

Bug: 7301742
Change-Id: Idd5074c2544b3238517655ab3c068966bae9f912
1 file changed