Reland of add a ClassID function to GrBatch

src/gpu/batches/GrStrokeRectBatch.h

Index: src/gpu/batches/GrStrokeRectBatch.h
diff --git a/src/gpu/batches/GrStrokeRectBatch.h b/src/gpu/batches/GrStrokeRectBatch.h
index b374ea862da84cc11ed843abb2887fea471e4420..b1cb8d4ccbe2642a7e69446bcfc1e474162e14cf 100644
--- a/src/gpu/batches/GrStrokeRectBatch.h
+++ b/src/gpu/batches/GrStrokeRectBatch.h
@@ -14,6 +14,8 @@
 
 class GrStrokeRectBatch : public GrVertexBatch {
 public:
+    DEFINE_BATCH_CLASS_ID
+
     struct Geometry {
         GrColor fColor;
         SkMatrix fViewMatrix;
@@ -74,6 +76,8 @@
 
     BatchTracker fBatch;
     SkSTArray<1, Geometry, true> fGeoData;
+
+    typedef GrVertexBatch INHERITED;
 };
 
 #endif