Revert of Convert //net and //chromecast to std::unordered_*

net/disk_cache/simple/simple_index.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/disk_cache/simple/simple_index.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 #include <utility>
@@ skipping 383 matching lines @@
   (*it)->second.SetEntrySize(entry_size);
 }
 
 void SimpleIndex::MergeInitializingSet(
     scoped_ptr<SimpleIndexLoadResult> load_result) {
   DCHECK(io_thread_checker_.CalledOnValidThread());
   DCHECK(load_result->did_load);
 
   EntrySet* index_file_entries = &load_result->entries;
 
-  for (std::unordered_set<uint64_t>::const_iterator it =
-           removed_entries_.begin();
+  for (base::hash_set<uint64_t>::const_iterator it = removed_entries_.begin();
        it != removed_entries_.end(); ++it) {
     index_file_entries->erase(*it);
   }
   removed_entries_.clear();
 
   for (EntrySet::const_iterator it = entries_set_.begin();
        it != entries_set_.end(); ++it) {
     const uint64_t entry_hash = it->first;
     std::pair<EntrySet::iterator, bool> insert_result =
         index_file_entries->insert(EntrySet::value_type(entry_hash,
@@ skipping 64 matching lines @@
                        start - last_write_to_disk_);
     }
   }
   last_write_to_disk_ = start;
 
   index_file_->WriteToDisk(entries_set_, cache_size_,
                            start, app_on_background_, base::Closure());
 }
 
 }  // namespace disk_cache