bluetoothd always send the GetManagedObjects() reply messages with the
objects array argument following an in-depth order starting from the
root. That means parents will always be known at the time their children
objects are parsed, if clients parse the objects in the same order they
appear in the array, as we do in PulseAudio.
This commit tries to protect PulseAudio in the case bluetoothd changes
that behavior for some reason. It hasn't been tested, since this
situation never occurs.
Create the pa_bluetooth_transport structure to store information about
the bluetooth transport and utility functions to manipulate this
structure. The acquire() and release() operations are function pointers
in the pa_bluetooth_transport structure to make possible for different
transport backends to provide different implementations of these
operations. Thre is also a userdata field for the transport backend
provide data for the acquire/release functions.
This commit also creates a new function
pa_bluetooth_device_any_transport_connected() to check if there is any
audio connection between the host and a remote device.
pa_bluetooth_discovery is the struct that holds information about known
Bluetooth audio devices and other information about the Bluetooth stack.
This commit also creates bluez5-util.[ch], which will hold a lot of
utility functions to help with the BlueZ 5 support.
