[WIP][Ozone] Support external touchscreens

ui/ozone/platform/dri/display_manager.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 UI_OZONE_PLATFORM_DRI_DISPLAY_MANAGER_H_
+#define UI_OZONE_PLATFORM_DRI_DISPLAY_MANAGER_H_
+
+#include <map>
+
+#include "base/macros.h"
+
+namespace ui {
+
+class DisplaySnapshot;
+
+class DisplayManager {
+ public:
+  DisplayManager();
+  ~DisplayManager();
+
+  void RegisterDisplay(DisplaySnapshot* display);
+  void UnregisterDisplay(DisplaySnapshot* display);
+
+  // Returns the display state for |display| or NULL if not found.
+  DisplaySnapshot* GetDisplay(int64_t display);
+
+ private:
+  typedef std::map<int64_t, DisplaySnapshot*> DisplayMap;
+
+  // Keeps a mapping between the display ID and a pointer to the display state.
+  DisplayMap display_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(DisplayManager);
+};
+
+}  // namespace ui
+
+#endif  // UI_OZONE_PLATFORM_DRI_DISPLAY_MANAGER_H_