all: Revert simultaneously walk fs and db on scan (fixes #4756) (#4757)

This reverts commit 6d3f9d5154.

lib/fs/walkfs.go

@@ -10,10 +10,7 @@
 
 package fs
 
-import (
-	"path/filepath"
-	"sort"
-)
+import "path/filepath"
 
 // WalkFunc is the type of the function called for each file or directory
 // visited by Walk. The path argument contains the argument to Walk as a
@@ -57,7 +54,6 @@ func (f *walkFilesystem) walk(path string, info FileInfo, walkFn WalkFunc) error
 	if err != nil {
 		return walkFn(path, info, err)
 	}
-	sort.Strings(names)
 
 	for _, name := range names {
 		filename := filepath.Join(path, name)