[Chrome OS Bootstrapping]: Do not always power off the Bluetooth adapter.

After the bootstrapping attempt is successful/failed, or the user has logged into the system,
power off the Bluetooth adapter only if the Bluetooth adapter was off before and there is no
connected Bluetooth type HID device.

BUG=chrome-os-partner:52828

Review-Url: https://codereview.chromium.org/1942883003
Cr-Commit-Position: refs/heads/master@{#391731}
10 files changed