Introduce a layering in the invalidation component as public and impl

components/invalidation/single_object_invalidation_set.h

-// Copyright 2014 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 COMPONENTS_INVALIDATION_SINGLE_OBJECT_INVALIDATION_SET_H_
-#define COMPONENTS_INVALIDATION_SINGLE_OBJECT_INVALIDATION_SET_H_
-
-#include <set>
-
-#include "base/memory/scoped_ptr.h"
-#include "components/invalidation/invalidation.h"
-#include "components/invalidation/invalidation_export.h"
-#include "components/invalidation/invalidation_util.h"
-
-namespace base {
-class ListValue;
-}  // namespace base
-
-namespace syncer {
-
-// Holds a list of invalidations that all share the same Object ID.
-//
-// The list is kept sorted by version to make it easier to perform common
-// operations, like checking for an unknown version invalidation or fetching the
-// highest invalidation with the highest version number.
-class INVALIDATION_EXPORT SingleObjectInvalidationSet {
- public:
-  typedef std::set<Invalidation, InvalidationVersionLessThan> InvalidationsSet;
-  typedef InvalidationsSet::const_iterator const_iterator;
-  typedef InvalidationsSet::const_reverse_iterator const_reverse_iterator;
-
-  SingleObjectInvalidationSet();
-  ~SingleObjectInvalidationSet();
-
-  void Insert(const Invalidation& invalidation);
-  void InsertAll(const SingleObjectInvalidationSet& other);
-  void Clear();
-  void Erase(const_iterator it);
-
-  // Returns true if this list contains an unknown version.
-  //
-  // Unknown version invalidations always end up at the start of the list,
-  // because they have the lowest possible value in the sort ordering.
-  bool StartsWithUnknownVersion() const;
-  size_t GetSize() const;
-  bool IsEmpty() const;
-  bool operator==(const SingleObjectInvalidationSet& other) const;
-
-  const_iterator begin() const;
-  const_iterator end() const;
-  const_reverse_iterator rbegin() const;
-  const_reverse_iterator rend() const;
-  const Invalidation& back() const;
-
-  scoped_ptr<base::ListValue> ToValue() const;
-  bool ResetFromValue(const base::ListValue& list);
-
- private:
-  InvalidationsSet invalidations_;
-};
-
-}  // syncer
-
-#endif  // COMPONENTS_INVALIDATION_SINGLE_OBJECT_INVALIDATION_SET_H_