[nullable] make the Eradicate flag use_models to be the default mode
[nullable] make the Eradicate flag use_models to be the default mode

Summary: There no clear alternative to using models of the standard library at this point so we can simplify the code a little bit

Reviewed By: mbouaziz

Differential Revision: D9491062

fbshipit-source-id: 9e5a6eeea

facebook/infer,facebook/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,jvillard/infer,facebook/infer,facebook/infer,jvillard/infer,jvillard/infer