Add ww logging for add creator token event

wtf is not appropriate for adding a creator token to an intent
because it is not an error. We simply want some statistics on
how often this happens and which app creats the intent.

Bug: 375396329
Test: statsd_testdrive 967
Flag: EXEMPT metrics
Change-Id: Iabf3d2b0fa0519f9910d69280e03e4d34910df71