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diff --git a/views/focus/external_focus_tracker.h b/views/focus/external_focus_tracker.h
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+// Copyright (c) 2006-2008 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 VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_
+#define VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_
+
+#include "views/focus/focus_manager.h"
+
+namespace views {
+
+class View;
+class ViewStorage;
+
+// ExternalFocusTracker tracks the last focused view which belongs to the
+// provided focus manager and is not either the provided parent view or one of
+// its descendants. This is generally used if the parent view want to return
+// focus to some other view once it is dismissed. The parent view and the focus
+// manager must exist for the duration of the tracking. If the focus manager
+// must be deleted before this object is deleted, make sure to call
+// SetFocusManager(NULL) first.
+//
+// Typical use: When a view is added to the view hierarchy, it instantiates an
+// ExternalFocusTracker and passes in itself and its focus manager. Then,
+// when that view wants to return focus to the last focused view which is not
+// itself and not a descandant of itself, (usually when it is being closed)
+// it calls FocusLastFocusedExternalView.
+class ExternalFocusTracker : public FocusChangeListener {
+ public:
+  ExternalFocusTracker(View* parent_view, FocusManager* focus_manager);
+
+  virtual ~ExternalFocusTracker();
+  // FocusChangeListener implementation.
+  virtual void FocusWillChange(View* focused_before, View* focused_now);
+
+  // Focuses last focused view which is not a child of parent view and is not
+  // parent view itself. Returns true if focus for a view was requested, false
+  // otherwise.
+  void FocusLastFocusedExternalView();
+
+  // Sets the focus manager whose focus we are tracking. |focus_manager| can
+  // be NULL, but no focus changes will be tracked. This is useful if the focus
+  // manager went away, but you might later want to start tracking with a new
+  // manager later, or call FocusLastFocusedExternalView to focus the previous
+  // view.
+  void SetFocusManager(FocusManager* focus_manager);
+
+ private:
+  // Store the provided view. This view will be focused when
+  // FocusLastFocusedExternalView is called.
+  void StoreLastFocusedView(View* view);
+
+  // Store the currently focused view for our view manager and register as a
+  // listener for future focus changes.
+  void StartTracking();
+
+  // Focus manager which we are a listener for.
+  FocusManager* focus_manager_;
+
+  // ID of the last focused view, which we store in view_storage_.
+  int last_focused_view_storage_id_;
+
+  // Used to store the last focused view which is not a child of
+  // ExternalFocusTracker.
+  ViewStorage* view_storage_;
+
+  // The parent view of views which we should not track focus changes to. We
+  // also do not track changes to parent_view_ itself.
+  View* parent_view_;
+
+  DISALLOW_EVIL_CONSTRUCTORS(ExternalFocusTracker);
+};
+
+}  // namespace views
+
+#endif  // VIEWS_FOCUS_EXTERNAL_FOCUS_TRACKER_H_