Bluetooth: Do not die quietly on binder death

Log if the Bluetooth service has died.
Also check the return status for Bluetooth service binder callbacks to
avoid DEAD_OBJECT exception when com.android.bluetooth crashes.

Bug: 36026072
Test: unit tests; Bluetooth off/on/off; kill -6 com.android.bluetooth
Change-Id: Ia28e6777ee7b78f06db8d5214324e696441d00f7