Root Cause: get empty result in hearingAidProfile.getConnectedDevices() Solution: Need to listen to onServiceConnected() to wait for HearingAidService get connected Bug: 243489972 Test: make RunSettingsRoboTests ROBOTEST_FILTER=AccessibilityHearingAidPreferenceControllerTest Change-Id: If6c3b2f3df81388c44e744e364e6258bde8bb645