How to Reproduce:
1) Create a new project from the HDRP template.
2) Enable VR and add the Oculus or OpenVR SDKs.
3) Enable Single Pass Double Wide
4) Change Rendering>Lit Shader Mode to Forward Only
5) Enable MSAA (Rendering>MSAA count not 'none').
6) Enable 'MSAA within Forward' from Default Frame Settings>Rendering

Expected Result: Eye texture is displayed correctly in both eyes.
Actual Result: Full eye texture is displayed in the left eye only.

Reproducible in: 2019.1.9f1 (d28f50652f6d)