Steps to reproduce:
1. Open the attached project (New Unity Project.zip)
2. Open the qq.unity scene
3. Open the Scene view
4. Select the text object in Scene view
5. Check Preferred Height in Layout Properties. Preferred Height is too small.

Expected result: PreferredHeight should return correct values
Actual result: PreferredHeight returns wrong values

Reproduced with: 5.5.0b11, 5.5.0f1, 5.5.0f2
Not reproduced with: 5.3.6p4, 5.4.2p3, 5.5.0b10
Regression introduced in 5.5.0b11