Summary:
- CSSLayoutSetLogger
- Problem: Unity or other logging system can't use printf output
- Solution: Add CSSLogger to pass CSSNodePrint result to UnityEngine.Debug.Log or other logging system via CSSLogger function for debugging purpose
Reviewed By: emilsjolander
Differential Revision: D4027044
fbshipit-source-id: 90e2e449260888770f71fa7ea790ca9764d91c44