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// 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 CHROME_BROWSER_UI_NATIVE_FOCUS_TRACKER_H_
#define CHROME_BROWSER_UI_NATIVE_FOCUS_TRACKER_H_

#include "base/basictypes.h"

class Browser;

// NativeFocusTracker is responsible for tracking changes to the active Browser
// and notifying NativeFocusTrackerHost of these changes. If a non-Browser
// window becomes active SetBrowser(NULL) should be invoked.
//
// ActiveTabTracker creates a NativeFocusTracker.
class NativeFocusTrackerHost {
 public:
  virtual void SetBrowser(Browser* browser) = 0;

 protected:
  virtual ~NativeFocusTrackerHost() {}
};

class NativeFocusTracker {
 public:
  virtual ~NativeFocusTracker() {}

  // Factory method, caller owns returned object.
  static NativeFocusTracker* Create(NativeFocusTrackerHost* host);

 protected:
  NativeFocusTracker() {}

 private:
  DISALLOW_COPY_AND_ASSIGN(NativeFocusTracker);
};

#endif  // CHROME_BROWSER_UI_NATIVE_FOCUS_TRACKER_H_