add a ClassID function to GrBatch

src/gpu/batches/GrAAStrokeRectBatch.h

Index: src/gpu/batches/GrAAStrokeRectBatch.h
diff --git a/src/gpu/batches/GrAAStrokeRectBatch.h b/src/gpu/batches/GrAAStrokeRectBatch.h
index ae7534823b421c2c19baa36b1fa8847995a3ebb4..1c00e905a7a31ae2744a3d28a7c47acd94d09155 100644
--- a/src/gpu/batches/GrAAStrokeRectBatch.h
+++ b/src/gpu/batches/GrAAStrokeRectBatch.h
@@ -27,6 +27,8 @@ public:
         bool fMiterStroke;
     };
 
+    BATCH_CLASS_ID
+
     static GrDrawBatch* Create(const Geometry& geometry, const SkMatrix& viewMatrix) {
         return new GrAAStrokeRectBatch(geometry, viewMatrix);
     }