Add undefined to records typespec

[varnerac]

I think this fixes the dialyzer issues, but I can't tell for sure. Referencing a fork of a fork to test it in Nucleus is a pain.

[evanmcc]

I don't think that this actually does what we want. Could you paste an example of the warning that you're trying to fix?

[varnerac]

It generates .hrl files like this:

-record(datapoint,
        {device_id = <<>>       :: iodata(),        % = 1
         change_id = 0          :: integer(),       % = 2, 32 bits
         datapoint_ts = 0       :: integer(),       % = 3, 32 bits
         battery = 0            :: integer(),       % = 4, 32 bits
         location = undefined   :: #location{},     % = 5
         proto_name = <<>>      :: iodata(),        % = 6
         proto_buffer = <<>>    :: binary(),        % = 7
         event_type = <<>>      :: iodata(),        % = 8
         packet_id = 0          :: integer(),       % = 9, 32 bits
         event_id = 0           :: integer(),       % = 10, 32 bits
         server_ts = 0          :: integer()        % = 11, 32 bits
        }).

The location field defaults to undefined, which breaks the declared type spec of #location{}

It should look like this:

         location = undefined   :: #location{} | undefined,     % = 5

[evanmcc]

OK, I see what you mean. I still don't think that your fix does the right thing. I'll add it to the list of stuff to fix when I finally get back to trying to get this merged upstream.