Console spams error "Invalid antiAliasing value (must be at least 1)" when we set antialiasing to "disabled" in quality settings and then select camera in the hierarchy.

Steps to Reproduce:
1. Create a new project.
2. Go to Project Settings >> Quality Settings >> Anti Aliasing >> Disabled
3. Select MainCamera in Hierarchy.

NOTE: "Invalid antiAliasing value (must be at least 1)" error spams in the console.

Expected Result:
An error should not appear in the console.

Actual Result :
An error is thrown at selecting a camera.

Frequency:
Always

Notes:
- Appears on both Windows and OSX
- On some Window and OSX machines, it doesn't appear. (Appeared on 3 out of 4 Windows and 2 out of 3 Mac machines with the same configuration.)

Reproduced on Unity 2018.1.0a2, 2018.1.0a3

Regression on Unity 2018.1.0a2

Not reproduced on Unity 5.6.4f1,2017.1.1f1, 2017.2.0f3 , 2017.3.0b8 , 2018.1.0a1

License type: Pro