Lockscreen Notifications: several fixes

- fix notification not responding when removed and added in a short period of time (e.g. gravity screen start/stop)
- just unlock screen on notification click when there's an activity to start
- fix notification hide animation
- just wake screen on reposted notifications when it's not ongoing (wake on notification before made the device stay awake for ever when a download/countdown or something similiar was running)

Conflicts:
	packages/Keyguard/src/com/android/keyguard/NotificationHostView.java

Change-Id: I094b7136f5eef248b53621a619f6919beb12157b