Add a Material Expansion example.

Authored by featherless on Mon, Mar 20, 2:21 PM.

Description

Add a Material Expansion example.

Reviewers: O2 Material Motion, O4 Material Apple platform reviewers, Material Motion, chuga

Reviewed By: O4 Material Apple platform reviewers, chuga

Tags: Material Motion

Differential Revision: http://codereview.cc/D2892