Make BluetoothConnectionCallback static

Tag: #refactor
Fixes: 180727461
Test: atest BluetoothInstrumentationTests
Change-Id: I4bd084cb6c0371b649adb1d1a65b3327ae3e488a
Merged-In: Id24a4b3a3510781d9105763b1722f44583a7fd7c
1 file changed