Revert 217768 "Adding key press detection in the browser process."

trunk/src/media/base/user_input_monitor.h

-// Copyright 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 MEDIA_BASE_USER_INPUT_MONITOR_H_
-#define MEDIA_BASE_USER_INPUT_MONITOR_H_
-
-#include <set>
-
-#include "base/memory/ref_counted.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
-#include "base/observer_list.h"
-#include "base/synchronization/lock.h"
-#include "media/base/media_export.h"
-#include "ui/base/events/event_constants.h"
-#include "ui/base/keycodes/keyboard_codes.h"
-
-struct SkIPoint;
-
-namespace base {
-class SingleThreadTaskRunner;
-}  // namespace base
-
-namespace media {
-
-// Monitors and notifies about mouse movements and keyboard events.
-// Thread safe. The thread on which the listenters are called is not guaranteed.
-// The callers should not perform expensive/blocking tasks in the callback since
-// it might be called on the browser UI/IO threads.
-class MEDIA_EXPORT UserInputMonitor {
- public:
-  // The interface to receive mouse movement events.
-  class MEDIA_EXPORT MouseEventListener {
-   public:
-    // |position| is the new mouse position.
-    virtual void OnMouseMoved(const SkIPoint& position) = 0;
-
-   protected:
-    virtual ~MouseEventListener() {}
-  };
-  // The interface to receive key stroke events.
-  class MEDIA_EXPORT KeyStrokeListener {
-   public:
-    // Called when any key is pressed. Called only once until the key is
-    // released, i.e. holding down a key for a long period will generate one
-    // callback just when the key is pressed down.
-    virtual void OnKeyStroke() = 0;
-
-   protected:
-    virtual ~KeyStrokeListener() {}
-  };
-
-  virtual ~UserInputMonitor();
-
-  // Creates a platform-specific instance of UserInputMonitor.
-  // |io_task_runner| is the task runner for an IO thread.
-  // |ui_task_runner| is the task runner for a UI thread.
-  static scoped_ptr<UserInputMonitor> Create(
-      const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
-      const scoped_refptr<base::SingleThreadTaskRunner>& ui_task_runner);
-
-  // The same |listener| should only be added once.
-  // The clients should make sure to call Remove*Listener before |listener| is
-  // destroyed.
-  void AddMouseListener(MouseEventListener* listener);
-  void RemoveMouseListener(MouseEventListener* listener);
-  void AddKeyStrokeListener(KeyStrokeListener* listener);
-  void RemoveKeyStrokeListener(KeyStrokeListener* listener);
-
- protected:
-  UserInputMonitor();
-
-  // Called by the platform-specific sub-classes to propagate the events to the
-  // listeners.
-  void OnMouseEvent(const SkIPoint& position);
-  void OnKeyboardEvent(ui::EventType event, ui::KeyboardCode key_code);
-
- private:
-  virtual void StartMouseMonitoring() = 0;
-  virtual void StopMouseMonitoring() = 0;
-  virtual void StartKeyboardMonitoring() = 0;
-  virtual void StopKeyboardMonitoring() = 0;
-
-  base::Lock lock_;
-  ObserverList<MouseEventListener, true> mouse_listeners_;
-  ObserverList<KeyStrokeListener, true> key_stroke_listeners_;
-  bool monitoring_mouse_;
-  bool monitoring_keyboard_;
-  // The set of keys currently held down. Used for convering raw keyboard events
-  // into KeyStrokeListener callbacks.
-  std::set<ui::KeyboardCode> pressed_keys_;
-
-  DISALLOW_COPY_AND_ASSIGN(UserInputMonitor);
-};
-
-}  // namespace media
-
-#endif  // MEDIA_BASE_USER_INPUT_MONITOR_H_