[unity] Fixed blend mode shaders being broken on Unity 2017. Closes #2212.

spine-unity/Assets/Spine/Runtime/spine-unity/Shaders/BlendModes/Spine-Skeleton-PMA-Additive.shader

@@ -44,6 +44,9 @@ Shader "Spine/Blend Modes/Skeleton PMA Additive" {
 		Pass {
 			Name "Normal"
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma shader_feature _ _STRAIGHT_ALPHA_INPUT
 			#include "../CGIncludes/Spine-BlendModes-NormalPass.cginc"
 			ENDCG
 		}
@@ -57,6 +60,10 @@ Shader "Spine/Blend Modes/Skeleton PMA Additive" {
 			ZTest LEqual
 
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma multi_compile_shadowcaster
+			#pragma fragmentoption ARB_precision_hint_fastest
 			#include "../CGIncludes/Spine-BlendModes-ShadowCasterPass.cginc"
 			ENDCG
 		}

spine-unity/Assets/Spine/Runtime/spine-unity/Shaders/BlendModes/Spine-Skeleton-PMA-Multiply.shader

@@ -44,6 +44,9 @@ Shader "Spine/Blend Modes/Skeleton PMA Multiply" {
 		Pass {
 			Name "Normal"
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma shader_feature _ _STRAIGHT_ALPHA_INPUT
 			#include "../CGIncludes/Spine-BlendModes-NormalPass.cginc"
 			ENDCG
 		}
@@ -57,6 +60,10 @@ Shader "Spine/Blend Modes/Skeleton PMA Multiply" {
 			ZTest LEqual
 
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma multi_compile_shadowcaster
+			#pragma fragmentoption ARB_precision_hint_fastest
 			#include "../CGIncludes/Spine-BlendModes-ShadowCasterPass.cginc"
 			ENDCG
 		}

spine-unity/Assets/Spine/Runtime/spine-unity/Shaders/BlendModes/Spine-Skeleton-PMA-Screen.shader

@@ -44,6 +44,9 @@ Shader "Spine/Blend Modes/Skeleton PMA Screen" {
 		Pass {
 			Name "Normal"
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma shader_feature _ _STRAIGHT_ALPHA_INPUT
 			#include "../CGIncludes/Spine-BlendModes-NormalPass.cginc"
 			ENDCG
 		}
@@ -57,6 +60,10 @@ Shader "Spine/Blend Modes/Skeleton PMA Screen" {
 			ZTest LEqual
 
 			CGPROGRAM
+			#pragma vertex vert
+			#pragma fragment frag
+			#pragma multi_compile_shadowcaster
+			#pragma fragmentoption ARB_precision_hint_fastest
 			#include "../CGIncludes/Spine-BlendModes-ShadowCasterPass.cginc"
 			ENDCG
 		}

spine-unity/Assets/Spine/Runtime/spine-unity/Shaders/CGIncludes/Spine-BlendModes-NormalPass.cginc

@@ -1,9 +1,6 @@
 #ifndef BLENDMODES_NORMAL_PASS_INCLUDED
 #define BLENDMODES_NORMAL_PASS_INCLUDED
 
-#pragma shader_feature _ _STRAIGHT_ALPHA_INPUT
-#pragma vertex vert
-#pragma fragment frag
 #include "UnityCG.cginc"
 #include "../CGIncludes/Spine-Common.cginc"
 uniform sampler2D _MainTex;

spine-unity/Assets/Spine/Runtime/spine-unity/Shaders/CGIncludes/Spine-BlendModes-ShadowCasterPass.cginc

@@ -1,10 +1,6 @@
 #ifndef BLENDMODES_SHADOWCASTER_PASS_INCLUDED
 #define BLENDMODES_SHADOWCASTER_PASS_INCLUDED
 
-#pragma vertex vert
-#pragma fragment frag
-#pragma multi_compile_shadowcaster
-#pragma fragmentoption ARB_precision_hint_fastest
 #include "UnityCG.cginc"
 struct v2f {
 	V2F_SHADOW_CASTER;