Backport hash collision workaround to 3.6.

src/heap.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5344 matching lines @@
   if (cell_space_ == NULL) return false;
   if (!cell_space_->Setup(NULL, 0)) return false;
 
   // The large object code space may contain code or data.  We set the memory
   // to be non-executable here for safety, but this means we need to enable it
   // explicitly when allocating large code objects.
   lo_space_ = new LargeObjectSpace(this, LO_SPACE);
   if (lo_space_ == NULL) return false;
   if (!lo_space_->Setup()) return false;
 
+  // Set up the seed that is used to randomize the string hash function.
+  ASSERT(string_hash_seed() == 0);
+  if (FLAG_randomize_string_hashes) {
+    if (FLAG_string_hash_seed == 0) {
+      set_string_hash_seed(
+          Smi::FromInt(V8::RandomPrivate(isolate()) & 0x3fffffff));
+    } else {
+      set_string_hash_seed(Smi::FromInt(FLAG_string_hash_seed));
+    }
+  }
+
   if (create_heap_objects) {
     // Create initial maps.
     if (!CreateInitialMaps()) return false;
     if (!CreateApiObjects()) return false;
 
     // Create initial objects
     if (!CreateInitialObjects()) return false;
 
     global_contexts_list_ = undefined_value();
   }
@@ skipping 900 matching lines @@
 }
 
 
 void ExternalStringTable::TearDown() {
   new_space_strings_.Free();
   old_space_strings_.Free();
 }
 
 
 } }  // namespace v8::internal