[sledge] Fix confusing arg naming
[sledge] Fix confusing arg naming

Summary: The existing code is simply confused.

Reviewed By: bennostein

Differential Revision: D37593407

fbshipit-source-id: 1199e111ba13816f629153ea988feda774ff7b08

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