Initial support for native accessibility in ARC

content/browser/accessibility/ax_tree_id_registry.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 CONTENT_BROWSER_ACCESSIBILITY_AX_TREE_ID_REGISTRY_H_
-#define CONTENT_BROWSER_ACCESSIBILITY_AX_TREE_ID_REGISTRY_H_
-
-#include <map>
-#include <utility>
-
-#include "base/macros.h"
-
-namespace base {
-template <typename T>
-struct DefaultSingletonTraits;
-}  // namespace base
-
-namespace content {
-
-// A class which generates a unique id given a process id and frame routing id.
-class AXTreeIDRegistry {
- public:
-  using FrameID = std::pair<int, int>;
-
-  using AXTreeID = int;
-
-  static const AXTreeID kNoAXTreeID;
-
-  // Get the single instance of this class.
-  static AXTreeIDRegistry* GetInstance();
-
-  // Obtains a unique id given a |process_id| and |routing_id|. Placeholder
-  // for full implementation once out of process iframe accessibility finalizes.
-  AXTreeID GetOrCreateAXTreeID(int process_id, int routing_id);
-  FrameID GetFrameID(AXTreeID ax_tree_id);
-  void RemoveAXTreeID(AXTreeID ax_tree_id);
-
- private:
-  friend struct base::DefaultSingletonTraits<AXTreeIDRegistry>;
-
-  AXTreeIDRegistry();
-  virtual ~AXTreeIDRegistry();
-
-  // Tracks the current unique ax frame id.
-  AXTreeID ax_tree_id_counter_;
-
-  // Maps an accessibility tree to its frame via ids.
-  std::map<AXTreeID, FrameID> ax_tree_to_frame_id_map_;
-
-  // Maps frames to an accessibility tree via ids.
-  std::map<FrameID, AXTreeID> frame_to_ax_tree_id_map_;
-
-  DISALLOW_COPY_AND_ASSIGN(AXTreeIDRegistry);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_ACCESSIBILITY_AX_TREE_ID_REGISTRY_H_