Reproduction steps:
1. Open the attached project;
2. Open the scene "AnchorPresetTesteScene";
3. Click Canvas -> Panel;
4. Change Anchor Preset and observe the label;

Actual result: the label always shows that is custom/custom Anchor Preset (actualResult.jpg).
Expected result: the label should show correct Anchor Preset which is set (expectedResult.jpg).

Note: the wrong Anchor Preset labels are shown with all UI objects.

Reproduced with: 5.6.0b1, 5.6.0f3, 2017.1.0a6
Not reproducible with: 5.5.3f1, 5.6.0a1
Regression introduced in 5.6.0b1