How to reproduce:
1. Create a new project
2. Add the attached "PrivateComponentProbe.cs" to Assets/Editor and select Tools > UITK Memory Repro > Empty viewDataKey
Expected results: No storage is created for an empty key, the same as for viewDataKey = null
Actual results: A VisualElementViewDataComponent is created for viewDataKey = "", the same as for a real key ("key"); a new element and viewDataKey = null have none
Reproducible with: 6000.7.0b3, 7000.0.0a12
Not reproducible with: 6000.7.0b2
Reproducible on: macOS 27.0.1 (M1 Max), Ubuntu 24.04.4 LTS
Not reproducible on: No other environment tested