Updated lightweight paths.

ScriptableRenderPipeline/LightweightPipeline/LWRP/Data/LightweightPipelineAsset.cs

 
     public class LightweightPipelineAsset : RenderPipelineAsset
     {
+        private const int PACKAGE_MANAGER_PATH_INDEX = 1;
         public static readonly string[] m_SearchPaths = {"Assets", "Packages/com.unity.render-pipelines.lightweight"};
 
         // Default values set when a new LightweightPipeline asset is created
                 // There's currently an issue that prevents FindAssets from find resources withing the package folder.
                 if (resourceAsset == null)
                 {
-                    string path = "Packages/com.unity.render-pipelines.lightweight/Data/LightweightPipelineResource.asset";
+                    string path = m_SearchPaths[PACKAGE_MANAGER_PATH_INDEX] + "/LWRP/Data/LightweightPipelineResource.asset";
                     resourceAsset = AssetDatabase.LoadAssetAtPath<LightweightPipelineResource>(path);
                 }
 

ScriptableRenderPipeline/LightweightPipeline/LWRP/Editor/LightweightShaderIncludePaths.cs

+using System.IO;
+
+namespace UnityEditor.Experimental.Rendering.LightweightPipeline
+{
+    static class LightweightIncludePaths
+    {
+        [ShaderIncludePath]
+        public static string[] GetPaths()
+        {
+            return new[]
+            {
+                Path.GetFullPath("Packages/com.unity.render-pipelines.lightweight/LWRP/Shaders"),
+            };
+        }
+    }
+}

ScriptableRenderPipeline/LightweightPipeline/LWRP/Editor/LightweightShaderIncludePaths.cs.meta

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