Avoid opening a nonexistent file and logging error
Avoid opening a nonexistent file and logging error

With dffe186953b6be27b7ba1ee402d8bc0a94f6626f, we log failed file
openings. When saving clojure.cljs in the Clojure plugin, I was
seeing these unnecessary errors as the plugin's clojurescript was
rebuilt

bruno-oliveira/LightTable,Bost/LightTable,LightTable/LightTable,sbauer322/LightTable,bruno-oliveira/LightTable,rundis/LightTable,sbauer322/LightTable,kenny-evitt/LightTable,sbauer322/LightTable,kenny-evitt/LightTable,LightTable/LightTable,bruno-oliveira/LightTable,Bost/LightTable,rundis/LightTable,rundis/LightTable,kenny-evitt/LightTable,Bost/LightTable,LightTable/LightTable