setGuidanceProvider
Stores the GuidanceProvider for Android Auto to use.
Called by phone app when:
Navigation starts while AA is connected
AA connects while navigation is active
The GuidanceProvider implementation (GuidanceProviderAdapter) handles:
Converting GuidanceState to AAGuidanceState
Converting Bitmap icons to ByteArrays
Delegating control actions to GuidanceViewModel
Parameters
provider
The GuidanceProvider instance, or null to clear