Consolidate handling of infinitely thin primitives and aa bloat handing WRT batch bounds

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 31 matching lines @@
     return MemoryPoolAccessor().pool()->allocate(size);
 }
 
 void GrBatch::operator delete(void* target) {
     return MemoryPoolAccessor().pool()->release(target);
 }
 
 GrBatch::GrBatch(uint32_t classID)
     : fClassID(classID)
     , fUniqueID(kIllegalBatchID) {
+    SkASSERT(classID == SkToU32(fClassID));
     SkDEBUGCODE(fUsed = false;)
+    SkDEBUGCODE(fBoundsFlags = kUninitialized_BoundsFlag);
 }
 
 GrBatch::~GrBatch() {}