Prevent crash when viewing person details

[cewert]

Caused by loss of connection to the server.

Comes from roku.com crash log:

'Dot' Operator attempted with invalid BrightScript Component or interface reference. (runtime error &hec) in pkg:/components/data/PersonData.brs(7) 
Backtrace: 
#0  Function setfields() As Voi$1 file/line: pkg:/components/data/PersonData.brs(7) 
Local Variables: 
global           Interface:ifGloba$1 m                roAssociativeArray refcnt=2 count:2 
json             Invalid

which points to this line after running build-prod on 2.1.4:

m.top.id = json.id

Issues

Ref #1164