Revert "Migrate the IndexedDB backend from Blink to Chromium"

content/browser/indexed_db/list_set.h

-// 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.
-
-#ifndef CONTENT_BROWSER_INDEXED_DB_LIST_SET_H_
-#define CONTENT_BROWSER_INDEXED_DB_LIST_SET_H_
-
-#include <algorithm>
-#include <iterator>
-#include <list>
-#include <set>
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-
-//
-// A container class that provides fast containment test (like a set)
-// but maintains insertion order for iteration (like list).
-//
-// Member types of value (primitives and objects by value), raw pointers
-// and scoped_refptr<> are supported.
-//
-template <typename T> class list_set {
- public:
-  list_set() {}
-  list_set(const list_set<T>& other) : list_(other.list_), set_(other.set_) {}
-  list_set& operator=(const list_set<T>& other) {
-    list_ = other.list_;
-    set_ = other.set_;
-    return *this;
-  }
-
-  void insert(const T& elem) {
-    if (set_.find(elem) != set_.end())
-      return;
-    set_.insert(elem);
-    list_.push_back(elem);
-  }
-
-  void erase(const T& elem) {
-    if (set_.find(elem) == set_.end())
-      return;
-    set_.erase(elem);
-    typename std::list<T>::iterator it =
-        std::find(list_.begin(), list_.end(), elem);
-    DCHECK(it != list_.end());
-    list_.erase(it);
-  }
-
-  bool has(const T& elem) { return set_.find(elem) != set_.end(); }
-
-  size_t size() const {
-    DCHECK_EQ(list_.size(), set_.size());
-    return set_.size();
-  }
-
-  bool empty() const {
-    DCHECK_EQ(list_.empty(), set_.empty());
-    return set_.empty();
-  }
-
-  class const_iterator;
-
-  class iterator {
-   public:
-    typedef iterator self_type;
-    typedef T value_type;
-    typedef T& reference;
-    typedef T* pointer;
-    typedef std::bidirectional_iterator_tag iterator_category;
-    typedef std::ptrdiff_t difference_type;
-
-    inline iterator(typename std::list<T>::iterator it) : it_(it) {}
-    inline self_type& operator++() {
-      ++it_;
-      return *this;
-    }
-    inline self_type operator++(int) {
-      self_type result(*this);
-      ++(*this);
-      return result;
-    }
-    inline self_type& operator--() {
-      --it_;
-      return *this;
-    }
-    inline self_type operator--(int) {
-      self_type result(*this);
-      --(*this);
-      return result;
-    }
-    inline value_type& operator*() { return *it_; }
-    inline value_type* operator->() { return &(*it_); }
-    inline bool operator==(const iterator& rhs) const { return it_ == rhs.it_; }
-    inline bool operator!=(const iterator& rhs) const { return it_ != rhs.it_; }
-
-    inline operator const_iterator() const { return const_iterator(it_); }
-
-   private:
-    typename std::list<T>::iterator it_;
-  };
-
-  class const_iterator {
-   public:
-    typedef const_iterator self_type;
-    typedef T value_type;
-    typedef T& reference;
-    typedef T* pointer;
-    typedef std::bidirectional_iterator_tag iterator_category;
-    typedef std::ptrdiff_t difference_type;
-
-    inline const_iterator(typename std::list<T>::const_iterator it) : it_(it) {}
-    inline self_type& operator++() {
-      ++it_;
-      return *this;
-    }
-    inline self_type operator++(int) {
-      self_type result(*this);
-      ++(*this);
-      return result;
-    }
-    inline self_type& operator--() {
-      --it_;
-      return *this;
-    }
-    inline self_type operator--(int) {
-      self_type result(*this);
-      --(*this);
-      return result;
-    }
-    inline const value_type& operator*() { return *it_; }
-    inline const value_type* operator->() { return &(*it_); }
-    inline bool operator==(const const_iterator& rhs) const {
-      return it_ == rhs.it_;
-    }
-    inline bool operator!=(const const_iterator& rhs) const {
-      return it_ != rhs.it_;
-    }
-
-   private:
-    typename std::list<T>::const_iterator it_;
-  };
-
-  iterator begin() { return iterator(list_.begin()); }
-  iterator end() { return iterator(list_.end()); }
-  const_iterator begin() const { return const_iterator(list_.begin()); }
-  const_iterator end() const { return const_iterator(list_.end()); }
-
- private:
-  std::list<T> list_;
-  std::set<T> set_;
-};
-
-// Prevent instantiation of list_set<scoped_ptr<T>> as the current
-// implementation would fail.
-// TODO(jsbell): Support scoped_ptr through specialization.
-template <typename T> class list_set<scoped_ptr<T> >;
-
-#endif  // CONTENT_BROWSER_INDEXED_DB_LIST_SET_H_