To reproduce:
1. Create a new Unity project
2. Import attached texture "groundGrass.png"
3. Make sure Texture Type is set to Sprite and open Sprite Editor
4. Select Edit Outline
5. Set Outline Tolerance to 0
6. Press Update/Generate

Expected result: generated outline has the same amount of points as in the older version of Unity
Actual result: generated outline has fewer points than in older version of Unity

Reproduced on:
2018.1.0b1 2018.1.5f12018.2.0b9 2018.3.0a2

Not reproduced on:
2017.3.2f1 2017.4.5f1 2018.1.0a5