KeyStore.reset changes

restore keystore reset behavior of removing master key.
otherwise after reboot keystore has is LOCKED and not UNINITIALIZED
	cmds/keystore/keystore.cpp

when removing password, reset the keystore, so it doesn't remain
locked with a now bogus password.

	core/java/com/android/internal/widget/LockPatternUtils.java

Change-Id: If5e0bb50b42599e9ca27a8b91d6cec12528419a1