`FlutterDevice.views` is limited by a filter. Pipe this filter up as an
option for the commands that instantiate `FlutterDevice`s. This is the
first change necessary for the CLI tooling to target specific isolates
(#22009).
More work needs to be done after this patch.
* Isolate names are dynamically generated and change every restart.
* This just filters views, not background isolates (`VMService.isolates`).