Enable flattening/unflattening with custom unflatten procs

tests/BitmapHeapTest.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBitmapHeap.h"
 #include "SkColor.h"
@@ skipping 70 matching lines @@
 
     // Now clear out the heap, after which it should be empty.
     heap.freeMemoryIfPossible(~0U);
     REPORTER_ASSERT(reporter, heap.count() == 0);
 
     // Now attempt to flatten the shader again.
     heap.deferAddingOwners();
     index = dictionary.find(*bitmapShader);
     heap.endAddingOwnersDeferral(false);
 
-    // The dictionary should report the same index since the new entry is identical.
     // The bitmap heap should contain the bitmap, but with no references.
-    REPORTER_ASSERT(reporter, 1 == index);
     REPORTER_ASSERT(reporter, heap.count() == 1);
     REPORTER_ASSERT(reporter, SkBitmapHeapTester::GetRefCount(heap.getEntry(0)) == 0);
 }