Crash with empty user primvars on a keyframe

[cpichard]

Describe the bug
The attached scene will crash arnold at frame 103.
The scene has a Points prim with keyframes. The keyframe 103 has the points but a user defined primvars:emptyarray is empty, which cause the crash.

To Reproduce
Steps to reproduce the behavior:

1. download the scene
2. run kick scene.usd -frame 103

Expected behavior
It shouldn't crash.

Used Software Versions

• Arnold: > 7.1.4
• USD: 22.11
  scene.usda.zip

[autodesk-oss-arnold-bot]

Issue synced internally to ARNOLD-13553