Merge pull request #1580 from Unity-Technologies/sg/fix-hd-meta-code-cuplication

Fix duplication of code from Surf to Vert in HDPBR Subshader meta generation

com.unity.render-pipelines.high-definition/HDRP/Editor/ShaderGraph/HDPBRSubShader.cs

                 PBRMasterNode.AlphaSlotId,
                 PBRMasterNode.AlphaThresholdSlotId
             },
-//             VertexShaderSlots = new List<int>()
-//             {
-//                 PBRMasterNode.PositionSlotId
-//             }
+            VertexShaderSlots = new List<int>()
+            {
+                //PBRMasterNode.PositionSlotId
+            }
         };
 
         Pass m_PassShadowCaster = new Pass()

com.unity.render-pipelines.high-definition/HDRP/Editor/ShaderGraph/HDUnlitSubShader.cs

             },
             VertexShaderSlots = new List<int>()
             {
-                PBRMasterNode.PositionSlotId
+                //PBRMasterNode.PositionSlotId
             }
         };
 

com.unity.shadergraph/CHANGELOG.md

 - Deserialization of subgraphs now works correctly.
 - Sub graphs are now suffixed with (sub), so you can tell them apart from other nodes.
 - The preview of a node does not obstruct the selection outliner anymore.
+- HD PBR subshader no longer duplicates surface description code into vertex shader.
 - You can now copy, paste, and duplicate sub-graph nodes with vector type input ports.
 - If the current render pipeline is not compatible, master nodes now display an error badge.
 - The preview shader now only considers the current render pipeline. Because of this there is less code to compile, and therefore the preview shader will compile faster.