symlink tests for MostFiles.deleteRecursivelyIfExists
symlink tests for MostFiles.deleteRecursivelyIfExists

Summary: Follow-up to D19783388 for better night sleep.

Reviewed By: gabrielrussoc

shipit-source-id: 261981dc19f4465ed128cbfa827e415d49632fab

nguyentruongtho/buck,kageiit/buck,kageiit/buck,facebook/buck,Addepar/buck,kageiit/buck,facebook/buck,JoelMarcey/buck,facebook/buck,Addepar/buck,JoelMarcey/buck,facebook/buck,facebook/buck,JoelMarcey/buck,Addepar/buck,nguyentruongtho/buck,Addepar/buck,JoelMarcey/buck,nguyentruongtho/buck,Addepar/buck,JoelMarcey/buck,nguyentruongtho/buck,facebook/buck,JoelMarcey/buck,kageiit/buck,Addepar/buck,JoelMarcey/buck,Addepar/buck,kageiit/buck,JoelMarcey/buck,nguyentruongtho/buck,Addepar/buck,Addepar/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,JoelMarcey/buck,kageiit/buck,Addepar/buck,kageiit/buck,nguyentruongtho/buck,nguyentruongtho/buck,Addepar/buck,JoelMarcey/buck,Addepar/buck,Addepar/buck,facebook/buck