[buck] also use the converted compdb paths before parsing
[buck] also use the converted compdb paths before parsing

Reviewed By: jvillard

Differential Revision: D19513337

fbshipit-source-id: c21f11d38

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