The Burndown Chart does not consider JIRA post function when calculating Remaining Estimate

To replicate

Set up the environment as follows:

1. Should be in a classic project (sprint-enabled) 
2. Workflow can be simple: Todo → In Progress → Done. (Best to edit a new workflow then activate it)
3. Whilst creating the "In Progress" → "Done" transition in this workflow, assign a screen to it. (The screen can be pre-existing).
   1. Modify this screen: add the "Log Work" field.
4. In this "In Progress" → "Done" transition, add a new post-function: "Update Issue Field" - setting "Remaining Estimate" to 0. Publish the workflow with these changes.

• (Current incorrect behaviour: If the post-function is the first in the list, then "Remaining Values" won't be updated and "Time Spent" will.)
• (Current incorrect behaviour: If the post-function is the last in the list, then "Time Spent" won't be updated and "Remaining Values" will.)

Then, perform the following actions:

1. Add a new issue to the sprint, of an issue type that the screen is assigned to.
2. Set the Original Estimate of this issue to 8h
3. On the board, drop this issue into the Done column following the workflow, the screen should appear. In the screen modal:
   1. Log in 4h work into Time Spent
   2. "Adjust automatically" should be checked for Remaining Estimate
4. On transition completion, the post-function from the workflow should then automatically set the Remaining Estimate to 0h

• Greenhopper does not understand that the Remaining Estimate had been decreased first by 4h and then by 4h again.

If the post-function of Update Issue Field is not used, the issue does not occur. Considering the post-function ships with the out-of-the-box, JIRA, it should take into consideration of setting the Remaining Estimate to 0.