[#1367] fstree: Add size hint for Delete

This allow to not to call `os.Stat` if caller already knows data size.

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/writecache/flush.go

@@ -123,7 +123,7 @@ func (c *cache) flushIfAnObjectExistsWorker(ctx context.Context, objInfo objectI
 		return
 	}
 
-	c.deleteFromDisk(ctx, objInfo.addr)
+	c.deleteFromDisk(ctx, objInfo.addr, uint64(len(res.RawData)))
 }
 
 func (c *cache) reportFlushError(msg string, addr string, err error) {
@@ -157,7 +157,7 @@ func (c *cache) flushFSTree(ctx context.Context, ignoreErrors bool) error {
 			return err
 		}
 
-		c.deleteFromDisk(ctx, e.Address)
+		c.deleteFromDisk(ctx, e.Address, uint64(len(e.ObjectData)))
 		return nil
 	}