add a ClassID function to GrBatch

src/gpu/batches/GrAAConvexPathRenderer.cpp

Index: src/gpu/batches/GrAAConvexPathRenderer.cpp
diff --git a/src/gpu/batches/GrAAConvexPathRenderer.cpp b/src/gpu/batches/GrAAConvexPathRenderer.cpp
index 75bf33279061ef3e0ad6cec712ee953b8a9eb20d..fce962474980f9746129aaa8581d292ed7419f66 100644
--- a/src/gpu/batches/GrAAConvexPathRenderer.cpp
+++ b/src/gpu/batches/GrAAConvexPathRenderer.cpp
@@ -733,6 +733,7 @@ static const GrGeometryProcessor* create_fill_gp(bool tweakAlphaForCoverage,
 
 class AAConvexPathBatch : public GrVertexBatch {
 public:
+    BATCH_CLASS_ID
     struct Geometry {
         GrColor fColor;
         SkMatrix fViewMatrix;
@@ -752,7 +753,6 @@ public:
     }
 
 private:
-
     void initBatchTracker(const GrPipelineOptimizations& opt) override {
         // Handle any color overrides
         if (!opt.readsColor()) {