Shader Variants: from 1 variant in Unity 4.7 to 721 variants in Unity 2017

Hi,


Old shaders from 4.7 with a single aariant now have 721 variants in 2017


How can I come back to a single Variant, or at worse One variant per Platform?



Shader "Mobile/Particles/AddTint"
{
Properties
{
_Tint("Tint", Color) = (1,1,1,1)
}
SubShader
{
Tags{ "Queue" = "Transparent" "RenderType" = "Transparent" "IgnoreProjector" = "True" }
ZWrite Off
Blend One One

Pass
{
CGPROGRAM

#pragma vertex vert
#pragma fragment frag

uniform half4 _Tint;

float4 vert(float4 vertexPos : POSITION) : SV_POSITION
{
#define UNITY_SHADER_NO_UPGRADE true
#if UNITY_VERSION >= 560
return UnityObjectToClipPos(vertexPos);
#else
return mul(UNITY_MATRIX_MVP, vertexPos);
#endif
}

half4 frag(void) : COLOR
{
return _Tint;
}
ENDCG
}
}
FallBack "Diffuse"
}