Refactor heap profiler's code to make possible including

src/heap-profiler.h

Index: src/heap-profiler.h
diff --git a/src/heap-profiler.h b/src/heap-profiler.h
index 90c664edee28eb927caa58b0481e338b09edb194..20ba457c5bf911b0248439181bf054713f58ef83 100644
--- a/src/heap-profiler.h
+++ b/src/heap-profiler.h
@@ -340,6 +340,7 @@ class AggregatedHeapSnapshot {
 
 
 class HeapEntriesMap;
+class HeapEntriesAllocator;
 class HeapSnapshot;
 
 class AggregatedHeapSnapshotGenerator {
@@ -354,7 +355,8 @@ class AggregatedHeapSnapshotGenerator {
   void CalculateStringsStats();
   void CollectStats(HeapObject* obj);
   template<class Iterator>
-  void IterateRetainers(HeapEntriesMap* entries_map);
+  void IterateRetainers(
+      HeapEntriesAllocator* allocator, HeapEntriesMap* entries_map);
 
   AggregatedHeapSnapshot* agg_snapshot_;
 };