Register Notification Memory Logging after boot completed

Based on statsd team recommendations, we probably shouldn't be talking
to stats service before LOCKED_BOOT_COMPLETED has triggered. This change
moves registration of statsd callbacks after that event.

Bug: 283841311
Test: using bugreports on panther
Change-Id: I6b3784990ad71b11af33ac790d3cb012f45679ff
3 files changed