Sort error after edit

[raineorshine]

Steps to Reproduce

- =sort
  - Alphabetical
    - Asc
- 1
- 2

1. Edit 1 to 3.
2. Toggle sort three times so that it clears the error and returns to sort/Alphabetical/Asc.

Current Behavior

1. The context appears to be sorted correctly, but sort icon indicates an error.

2. The sort order is incorrect:

- =sort
  - Alphabetical
    - Asc
- 3
- 2

Expected Behavior

1. No error.
2. The thoughts should be sorted in ascending order:

- =sort
  - Alphabetical
    - Asc
- 2
- 3

Testing

Add an appropriate test for each step (two tests total).