Adding key press detection in the browser process.

media/base/user_input_monitor.h

Index: media/base/user_input_monitor.h
diff --git a/media/base/user_input_monitor.h b/media/base/user_input_monitor.h
new file mode 100644
index 0000000000000000000000000000000000000000..3fea358c13e1c5b666e592540fa0e8a1be36c19a
--- /dev/null
+++ b/media/base/user_input_monitor.h
@@ -0,0 +1,67 @@
+// 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 MEDIA_BASE_USER_INPUT_MONITOR_H_
+#define MEDIA_BASE_USER_INPUT_MONITOR_H_
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.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 {
+
+// Called on the |observer_task_runner|.
+class UserInputObserver {
+ public:
+  // Called when the mouse is moved.
+  virtual void OnMouseMoved(const SkIPoint& position) = 0;
+  // Called when a key is pressed or released.
+  // |event| can only be ui::ET_KEY_PRESSED or ui::ET_KEY_RELEASED.
+  virtual void OnKeyboardEvent(ui::EventType event,
+                               ui::KeyboardCode key_code) = 0;
+};

[DaleCurtis, 2013/08/07 18:58:02]

Needs protected virtual destructor with empty impl.

+
+// Monitors and notifies about mouse movements and keyboard events.
+class UserInputMonitor {
+ public:
+  // Bit masks for specifying input events of interest.
+  enum InputEvent {
+    MOUSE_MOVEMENT = 0x1,
+    KEYBOARD_EVENT = 0x2,
+  };
+
+  virtual ~UserInputMonitor() {}

[DaleCurtis, 2013/08/07 18:58:02]

protected.

+
+  // Creates a platform-specific instance of UserInputMonitor.
+  // |input_task_runner| is the task runner for an IO thread to process events

[DaleCurtis, 2013/08/07 18:58:02]

You mention mac / linux / win here, but it's a generic platform agnostic
interface. It sounds like there should just be an input_task_runner which the
caller specifies as IO on linux and UI on mac / win?

+  // on Linux; |ui_task_runner| is the task runner for a UI thread to process
+  // events on Mac and Windows.
+  // |observer_task_runner| is the task runner to run callbacks to the
+  // |observer|.
+  // |events_of_interests| specifies the events the caller is interested to
+  // receive notifications for.
+  // |observer| is the notification receiver and dereferenced on the
+  // |observer_task_runner|.
+  static scoped_ptr<UserInputMonitor> Create(
+      scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,

[DaleCurtis, 2013/08/07 18:58:02]

const & ? ditto for the other two.

+      scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> observer_task_runner,
+      uint8 events_of_interest,

[DaleCurtis, 2013/08/07 18:58:02]

input_event_mask ?

+      base::WeakPtr<UserInputObserver> observer);
+
+ protected:
+  UserInputMonitor() {}
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_USER_INPUT_MONITOR_H_