Merge r9123 into 3.5 branch. This fixes DevTools crash on large heap snapshots.

src/profile-generator.h

Index: src/profile-generator.h
===================================================================
--- src/profile-generator.h	(revision 9125)
+++ src/profile-generator.h	(working copy)
@@ -654,6 +654,7 @@
   HeapEntry* gc_roots() { return gc_roots_entry_; }
   HeapEntry* natives_root() { return natives_root_entry_; }
   List<HeapEntry*>* entries() { return &entries_; }
+  int raw_entries_size() { return raw_entries_size_; }
 
   void AllocateEntries(
       int entries_count, int children_count, int retainers_count);
@@ -689,9 +690,7 @@
   char* raw_entries_;
   List<HeapEntry*> entries_;
   bool entries_sorted_;
-#ifdef DEBUG
   int raw_entries_size_;
-#endif
 
   friend class HeapSnapshotTester;
 
@@ -1097,6 +1096,7 @@
   }
 
   void EnumerateNodes();
+  HeapSnapshot* CreateFakeSnapshot();
   int GetNodeId(HeapEntry* entry);
   int GetStringId(const char* s);
   void SerializeEdge(HeapGraphEdge* edge);
@@ -1108,6 +1108,8 @@
   void SerializeStrings();
   void SortHashMap(HashMap* map, List<HashMap::Entry*>* sorted_entries);
 
+  static const int kMaxSerializableSnapshotRawSize;
+
   HeapSnapshot* snapshot_;
   HashMap nodes_;
   HashMap strings_;