Fixed HDRP variant

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Editor/BuildPlayer/HDRPVariantStripper.cs

             // Do we have a shader variant stripper function for this shader?
             VariantStrippingFunc stripperFunc = null;
             m_StripperFuncs.TryGetValue(shader.name, out stripperFunc);
-            if (stripperFunc == null)
+            if (stripperFunc == null || inputData.Count == 0)
-            int inputShaderVariantCount = inputData.Count;
-
-            ShaderCompilerData workaround = inputData[0];
+            var workaround = inputData[0];
 
             for (int i = 0; i < inputData.Count; ++i)
             {