Grab pass + VR is Broken

I’m trying to update my project from Unity 5.5.4p4 to Unity 2017.2.0b11 (I need this to target Windows MR)
I’m stuck with a problem with some shaders that use Grab pass.
To illustrate the problem I’ve created this simple project.
It includes the SteamVR 1.2.2 plugin.
In the scene I have the SteamVR Camera Rig prefab, some cubes and a Plane that has a material with the following shader on it (that I’ve created with Shader Forge):

Shader "Shader Forge/test" {
    Properties {
    }
    SubShader {
        Tags {
            "IgnoreProjector"="True"
            "Queue"="Transparent"
            "RenderType"="Transparent"
        }
        GrabPass{ }
        Pass {
            Name "FORWARD"
            Tags {
                "LightMode"="ForwardBase"
            }
            ZWrite Off
           
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #define UNITY_PASS_FORWARDBASE
            #include "UnityCG.cginc"
            #pragma multi_compile_fwdbase
            #pragma only_renderers d3d9 d3d11 glcore gles
            #pragma target 3.0
            uniform sampler2D _GrabTexture;
            struct VertexInput {
                float4 vertex : POSITION;
                float2 texcoord0 : TEXCOORD0;
            };
            struct VertexOutput {
                float4 pos : SV_POSITION;
                float2 uv0 : TEXCOORD0;
                float4 projPos : TEXCOORD1;
            };
            VertexOutput vert (VertexInput v) {
                VertexOutput o = (VertexOutput)0;
                o.uv0 = v.texcoord0;
                o.pos = UnityObjectToClipPos( v.vertex );
                o.projPos = ComputeScreenPos (o.pos);
                COMPUTE_EYEDEPTH(o.projPos.z);
                return o;
            }
            float4 frag(VertexOutput i) : COLOR {
                float2 sceneUVs = (i.projPos.xy / i.projPos.w);
                float4 sceneColor = tex2D(_GrabTexture, sceneUVs);
////// Lighting:
////// Emissive:
                float3 emissive = tex2D( _GrabTexture, i.uv0).rgb;
                float3 finalColor = emissive;
                return fixed4(finalColor,1);
            }
            ENDCG
        }
    }
    FallBack "Diffuse"
    CustomEditor "ShaderForgeMaterialInspector"
}

Running this project on Unity 5.5.4p4 I see this view of the Plane in the game viewport:

Running the same project on Unity 2017.2.0b11 gives me this view:

As you can see, in 2017 we only see one eye (with some black bars) instead of both eyes.

Hi matan_onehamsa,
Could you please file a bug report with a minimal reproduction case and reply in here with the case #?

I already did, here is the case number:
Case 953360

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