Removed Lightweight Particles shaders as now the lightweight pipeline supports Unity vanilla particle shaders.

ScriptableRenderPipeline/LightweightPipeline/Editor/LegacyShadersToLightweightPipelineUpgrader.cs

             materialUpgraders.Add(new LegacyBlinnPhongUpgrader("Mobile/Bumped Diffuse", SupportedUpgradeParams.diffuseOpaque));
             materialUpgraders.Add(new LegacyBlinnPhongUpgrader("Mobile/Unlit (Supports Lightmap)", SupportedUpgradeParams.diffuseOpaque));
             materialUpgraders.Add(new LegacyBlinnPhongUpgrader("Mobile/VertexLit", SupportedUpgradeParams.specularOpaque));
-
-            /////////////////////////////////////
-            // Particles                        /
-            /////////////////////////////////////
-            materialUpgraders.Add(new ParticlesAdditiveUpgrader("Particles/Additive"));
-            materialUpgraders.Add(new ParticlesAdditiveUpgrader("Mobile/Particles/Additive"));
-            materialUpgraders.Add(new ParticlesMultiplyUpgrader("Particles/Multiply"));
-            materialUpgraders.Add(new ParticlesMultiplyUpgrader("Mobile/Particles/Multiply"));
         }
     }
 }

ScriptableRenderPipeline/LightweightPipeline/Editor/LightweightPipelineUpgraders.cs

         }
     }
 
-    public class ParticlesMultiplyUpgrader : MaterialUpgrader
-    {
-        public ParticlesMultiplyUpgrader(string oldShaderName)
-        {
-            RenameShader(oldShaderName, "ScriptableRenderPipeline/LightweightPipeline/Particles/Multiply");
-        }
-    }
-
-    public class ParticlesAdditiveUpgrader : MaterialUpgrader
-    {
-        public ParticlesAdditiveUpgrader(string oldShaderName)
-        {
-            RenameShader(oldShaderName, "ScriptableRenderPipeline/LightweightPipeline/Particles/Additive");
-        }
-    }
-
     public class StandardUpgrader : MaterialUpgrader
     {
         public StandardUpgrader(string oldShaderName)

ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightParticlesAdd.shader.meta

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-timeCreated: 1490023099
-licenseType: Pro
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-  defaultTextures: []
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightParticlesMultiply.shader.meta

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-licenseType: Pro
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ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightParticlesAdd.shader

-Shader "ScriptableRenderPipeline/LightweightPipeline/Particles/Additive"
-{
-    Properties
-    {
-        _MainTex("Particle Texture", 2D) = "white" {}
-    }
-
-    Category
-    {
-        Tags{"Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" "RenderPipeline" = "LightweightPipeline" "PreviewType" = "Plane"}
-        Blend SrcAlpha One
-        Cull Off Lighting Off ZWrite Off
-
-        SubShader
-        {
-            Pass
-            {
-                Tags{"LightMode" = "LightweightForward"}
-                CGPROGRAM
-                #pragma vertex vert
-                #pragma fragment frag
-                #pragma target 2.0
-                #pragma multi_compile_fog
-
-                #include "UnityCG.cginc"
-
-                sampler2D _MainTex;
-
-                struct appdata_t
-                {
-                    float4 vertex : POSITION;
-                    fixed4 color : COLOR;
-                    float2 texcoord : TEXCOORD0;
-                };
-
-                struct v2f
-                {
-                    float4 vertex : SV_POSITION;
-                    fixed4 color : COLOR;
-                    float2 texcoord : TEXCOORD0;
-                    UNITY_FOG_COORDS(1)
-                };
-
-                float4 _MainTex_ST;
-
-                v2f vert(appdata_t v)
-                {
-                    v2f o;
-                    o.vertex = UnityObjectToClipPos(v.vertex);
-
-                    o.color = v.color;
-                    o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);
-                    UNITY_TRANSFER_FOG(o,o.vertex);
-                    return o;
-                }
-
-                fixed4 frag(v2f i) : SV_Target
-                {
-                    fixed4 col = 2.0f * i.color * tex2D(_MainTex, i.texcoord);
-                    UNITY_APPLY_FOG_COLOR(i.fogCoord, col, fixed4(0,0,0,0)); // fog towards white due to our blend mode
-                    return col;
-                }
-                ENDCG
-            }
-        }
-    }
-}

ScriptableRenderPipeline/LightweightPipeline/Shaders/LightweightParticlesMultiply.shader

-Shader "ScriptableRenderPipeline/LightweightPipeline/Particles/Multiply"
-{
-    Properties
-    {
-        _MainTex("Particle Texture", 2D) = "white" {}
-    }
-
-    Category
-    {
-        Tags{"Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" "RenderPipeline" = "LightweightPipeline" "PreviewType" = "Plane"}
-        Blend Zero SrcColor
-        Cull Off Lighting Off ZWrite Off
-
-        SubShader
-        {
-            Pass
-            {
-                Tags { "LightMode" = "LightweightForward" }
-                CGPROGRAM
-                #pragma vertex vert
-                #pragma fragment frag
-                #pragma target 2.0
-                #pragma multi_compile_fog
-
-                #include "UnityCG.cginc"
-
-                sampler2D _MainTex;
-
-                struct appdata_t
-                {
-                    float4 vertex : POSITION;
-                    fixed4 color : COLOR;
-                    float2 texcoord : TEXCOORD0;
-                };
-
-                struct v2f
-                {
-                    float4 vertex : SV_POSITION;
-                    fixed4 color : COLOR;
-                    float2 texcoord : TEXCOORD0;
-                    UNITY_FOG_COORDS(1)
-                };
-
-                float4 _MainTex_ST;
-
-                v2f vert(appdata_t v)
-                {
-                    v2f o;
-                    o.vertex = UnityObjectToClipPos(v.vertex);
-                    o.color = v.color;
-                    o.texcoord = TRANSFORM_TEX(v.texcoord,_MainTex);
-                    UNITY_TRANSFER_FOG(o,o.vertex);
-                    return o;
-                }
-
-                fixed4 frag(v2f i) : SV_Target
-                {
-                    half4 prev = i.color * tex2D(_MainTex, i.texcoord);
-                    fixed4 col = lerp(half4(1,1,1,1), prev, prev.a);
-                    UNITY_APPLY_FOG_COLOR(i.fogCoord, col, fixed4(1,1,1,1)); // fog towards white due to our blend mode
-                    return col;
-                }
-                ENDCG
-            }
-        }
-    }
-}