Add repeatSpan and change interface name.

src/core/SkLinearBitmapPipeline.h

Index: src/core/SkLinearBitmapPipeline.h
diff --git a/src/core/SkLinearBitmapPipeline.h b/src/core/SkLinearBitmapPipeline.h
index f8978a7435b793207f76622f94b2d38648e54d50..e304ef85e718ef0407539940502eca0ea2d699c1 100644
--- a/src/core/SkLinearBitmapPipeline.h
+++ b/src/core/SkLinearBitmapPipeline.h
@@ -60,13 +60,13 @@ public:
     };
 
     class PointProcessorInterface;
-    class BilerpProcessorInterface;
+    class SampleProcessorInterface;
     class PixelPlacerInterface;
 
     // These values were generated by the assert above in PolymorphicUnion.
     using MatrixStage = PolymorphicUnion<PointProcessorInterface, 160>;
     using TileStage   = PolymorphicUnion<PointProcessorInterface, 160>;
-    using SampleStage = PolymorphicUnion<BilerpProcessorInterface,100>;
+    using SampleStage = PolymorphicUnion<SampleProcessorInterface,100>;
     using PixelStage  = PolymorphicUnion<PixelPlacerInterface,     80>;
 
 private: