Root Cause: Media type Audio output has inconsistent result with Output Switcher, and it needs to be resolved from Audio Policies API.
Please see more details in b/279003337.
Solution: Remove 'Media' type in Android U temporary.
Bug: 283907809
Test: flash rom & check UI
Change-Id: Id64866f7dc12ca5429e0b961cbafe51329b4eef1
* Extract the common part into HearingAidHelper.
* Remove abstract getHearingDevice(). Change to get the hearing device when needed.
* Move several classes from Bluetooth into Accessibility
Bug: 281783079
Test: make RunSettingsRoboTests ROBOTEST_FILTER="(HearingDeviceAudioRoutingBasePreferenceControllerTest|AccessibilityHearingAidPreferenceControllerTest|HearingAidHelperTest|HearingAidAudioRoutingPreferenceControllerTest|HearingDeviceCallRoutingPreferenceControllerTest)"
Change-Id: I79049107409b7086c6dcc8d48a6323e171ed1535