API proposal for chrome.app.window to intercept all keys.

chrome/browser/ui/views/apps/desktop_keyboard_capture.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 CHROME_BROWSER_UI_VIEWS_APPS_DESKTOP_KEYBOARD_CAPTURE_H_
+#define CHROME_BROWSER_UI_VIEWS_APPS_DESKTOP_KEYBOARD_CAPTURE_H_
+
+#include "ui/views/widget/widget.h"
+#include "ui/views/widget/widget_observer.h"
+
+// This class installs/uninstalls keyboard hook as the widget activation
+// changes.
+class DesktopKeyboardCapture : public views::WidgetObserver {
+ public:
+  explicit DesktopKeyboardCapture(views::Widget* widget);
+  ~DesktopKeyboardCapture();
+
+ private:
+  // views::WidgetObserver implementation.
+  void OnWidgetActivationChanged(views::Widget* widget, bool active) override;
+
+  void RegisterKeyboardHooks();
+  void DeregisterKeyboardHooks();
+
+  // The widget registering for keyboard intercept. Weak reference.
+  views::Widget* widget_;
+
+  // Current state of keyboard intercept registration.
+  bool is_registered_;
+
+  DISALLOW_COPY_AND_ASSIGN(DesktopKeyboardCapture);
+};
+
+#endif  // CHROME_BROWSER_UI_VIEWS_APPS_DESKTOP_KEYBOARD_CAPTURE_H_