"Remapped Materials" section is missing under the Materials tab when preset is created of any 3D model.

Steps to reproduce:
1. Open the attached project or create new.
2. Import any 3D model in the project.
3. Click on the preset icon in the inspector.
4. Click on 'Save current to..' on Select Preset window and save the preset.
5. Compare 3D model Material properties and it's preset Material properties in the inspector window.

Actual Result:
"Remapped Materials" section is missing when preset is created of any 3D model.

Expected Result:
"Remapped Materials" should be available when preset is created of any 3D model.

Occuring on : 2019.1.0a9, 2018.3.0b11, 2018.3.0a5

Working fine on: 2018.3.a2, 2018.2.0f2

Environment: Windows and Mac

Note :
1. In 2018.3.0a3 and 2018.3.0a4 3D model's Import Materials are missing under the Material tab and "NullReferenceException" thrown in console.

2. "Root node" drop-down menus are missing under the Rig tab when preset is created of any FBX 3D model.