add a ClassID function to GrBatch

src/gpu/batches/GrDrawAtlasBatch.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrDrawAtlasBatch_DEFINED
 #define GrDrawAtlasBatch_DEFINED
 
 #include "GrColor.h"
 #include "GrDefaultGeoProcFactory.h"
 #include "GrVertexBatch.h"
 
 class GrDrawAtlasBatch : public GrVertexBatch {
 public:
+    DEFINE_BATCH_CLASS_ID
+
     struct Geometry {
         GrColor                 fColor;
         SkTArray<uint8_t, true> fVerts;
     };
-    
+
     static GrDrawBatch* Create(const Geometry& geometry, const SkMatrix& viewMatrix,
                                int spriteCount, const SkRSXform* xforms, const SkRect* rects,
                                const SkColor* colors) {
         return new GrDrawAtlasBatch(geometry, viewMatrix, spriteCount, xforms, rects, colors);
     }
     
     const char* name() const override { return "DrawAtlasBatch"; }
     
     void getInvariantOutputColor(GrInitInvariantOutput* out) const override {
         // When this is called on a batch, there is only one geometry bundle
@@ skipping 27 matching lines @@
     
     bool onCombineIfPossible(GrBatch* t, const GrCaps&) override;
     SkSTArray<1, Geometry, true> fGeoData;
     
     SkMatrix fViewMatrix;
     GrColor  fColor;
     int      fQuadCount;
     bool     fColorIgnored;
     bool     fCoverageIgnored;
     bool     fHasColors;
+
+    typedef GrVertexBatch INHERITED;
 };
 
 #endif