Revert "Revert "Logging: Bluetooth Enabled""

This reverts commit 46850eb3.

Reason for revert: The dummy StatsLog class was merged into stage-aosp-master and oc-mr1-dev-plus-aosp, which were the branches that broke initially.

Change-Id: Iab9bac487d845db0ba70b2622679523604b4944e