Only move selected documents in Ordered Folder

Steps to reproduce:

• Create an Ordered Folder
• Fill folder with several documents
• Select several documents that are not grouped together
• Using the up and down arrows, move the selection several times in different directions.
• Deselect all but one of the currently selected documents.
• Select one other document
• Using the up and down arrows, start moving the selection again.
  => One of the previously selected documents is being moved instead of all of the selected documents.

This error only happens randomly.

Edit: These specific steps successfully reproduce the error every time:

Steps to reproduce:

• Create an Ordered Folder
• Fill folder with several File documents in the following order:
  • Apple
  • Grape
  • Banana
  • Avocado
  • Kumquat
  • Orange
  • Melon
  • Pear
  • Kiwi
• Select Grape, Avocado, Orange and Pear
• Click on the Move Up button
• Click on the Move Down button
• Keep selected files but select Kiwi also.
• Click the Move Down button.
• Deselect Avocado and Orange.
• Click the Move Up button.
• Select Kumquat, Melon and Avocado.
• Click the Move Up button.
• Deselect everything except for Kumquat.
• Select Banana.
• Click the Move Down button.
  => Kumquat does not move.
• Keep clicking Move Down or Move Up button.
  => Banana moves, but Kumquat still doesn't move.

Expected behavior: Kumquat should move down to join Banana.