dvAndroidStateDirectory function
Where the device runtime keeps its id, provisioning record and restarts, given the application's own files directory. Null when there is none.
The shared runtime falls back to $HOME and then to
Directory.systemTemp. Android has neither: HOME is unset and /tmp
belongs to no application, so device.health would throw on its first
call — on the phone, and nowhere it was tested. Null for an empty
directory rather than a path at the root of the device, which is a write
that fails from a line that reads like a join.
Implementation
String? dvAndroidStateDirectory(String? filesDir) =>
_dvAndroidUnder(filesDir, 'dartvel-device');