2D Polygon collider does not fit open ended sprite shape

Repro steps:
1. Download and open the attached "Polygon fail example.zip" project
2. In SampleScene, select "Open Sprite Shape" in Hierarchy
3. Observe the game object's collider in the Scene view

Expected result: The game object's collider is extended to the end of the open sprite shape edges
Actual result: The game object's collider is not extended to the end of the open sprite shape edges