Revert of add a ClassID function to GrBatch

src/gpu/batches/GrBatch.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrBatch.h"
 
 #include "GrMemoryPool.h"
@@ skipping 28 matching lines @@
 GrBATCH_SPEW(int32_t GrBatch::gCurrBatchUniqueID = GrBatch::kIllegalBatchID;)
 
 void* GrBatch::operator new(size_t size) {
     return MemoryPoolAccessor().pool()->allocate(size);
 }
 
 void GrBatch::operator delete(void* target) {
     return MemoryPoolAccessor().pool()->release(target);
 }
 
-GrBatch::GrBatch(uint32_t classID)
-    : fClassID(classID)
+GrBatch::GrBatch()
+    : fClassID(kIllegalBatchID)
 #if GR_BATCH_SPEW
-    , fUniqueID(GenBatchID())
+    , fUniqueID(GenID(&gCurrBatchUniqueID))
 #endif
 {
     SkDEBUGCODE(fUsed = false;)
 }
 
 GrBatch::~GrBatch() {}