Don't clear notification LEDs when seeing notifications on the lockscreen. Also fix a bug where the LED didn't continue flashing after the screen turned off. For devices with doze capability, ensure that the LED continuing to flash after screen off doesn't cause an immediate pulses, but delay the first pulse by 10s. Bug: 15449039 Change-Id: Id34d51a2c91ceaf069e49add1ab690bb855f9638