GrFP can express distance vector field req., program builder declares variable for it

src/gpu/GrPipeline.h

Index: src/gpu/GrPipeline.h
diff --git a/src/gpu/GrPipeline.h b/src/gpu/GrPipeline.h
index a17eb098cf4bc1edc046aaaf7c7ba775f84ef0fa..6795ef7368fe8ecef836496cbba530f1dd83d44f 100644
--- a/src/gpu/GrPipeline.h
+++ b/src/gpu/GrPipeline.h
@@ -156,10 +156,14 @@ public:
     bool getAllowSRGBInputs() const {
         return SkToBool(fFlags & kAllowSRGBInputs_Flag);
     }
+    bool usesDistanceVectorField() const {
+        return SkToBool(fFlags & kUsesDistanceVectorField_Flag);
+    }
     bool hasStencilClip() const {
         return SkToBool(fFlags & kHasStencilClip_Flag);
     }
 
+
     GrXferBarrierType xferBarrierType(const GrCaps& caps) const {
         return this->getXferProcessor().xferBarrierType(fRenderTarget.get(), caps);
     }
@@ -202,7 +206,8 @@ private:
         kSnapVertices_Flag                  = 0x2,
         kDisableOutputConversionToSRGB_Flag = 0x4,
         kAllowSRGBInputs_Flag               = 0x8,
-        kHasStencilClip_Flag                = 0x10
+        kUsesDistanceVectorField_Flag       = 0x10,
+        kHasStencilClip_Flag                = 0x20,
     };
 
     typedef GrPendingIOResource<GrRenderTarget, kWrite_GrIOType> RenderTarget;