Steps to reproduce:
1. Create a new project
2. Import Shader graph package
3. Create a shader graph
4. Add "Texture 2D Array Asset" Node to shader graph
5. Select "Texture 2D Array" object field and press Space Bar

Expected results: Just the Object selection window opens
Actual results: Objects selection window and Shader graph search window opens

Reproduced with: 2019.3.0a12, 2019.2.1f1, 2019.1.14f1
Not reproducible with: 2018.4.14f1

Reproduced with Shader graph package: 7.0.1, 6.9.1, 5.7.2
Not reproducible with: 4.10.0 (Opens just Shader graph search window)