Description:
Pressing backspace when the caret is at the beginning of a nested list item does not "outdent" the list item. Rather, it merges the list item to the preceding list item.

Steps to reproduce:

1. Create a nested list
2. Place caret at the start of an indented list item
3. Press [Backspace]

Expected behavior:
The indented list item should outdent one level with each press of [Backspace], and only merge with the preceding item after it is fully outdented.

Screencast:

Actual behavior:
The indented list item immediately merges with the preceding list item.

Screencast: