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

chrome/browser/ui/views/apps/keyboard_hook_handler.cc

+// 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.
+
+#include "chrome/browser/ui/views/apps/keyboard_hook_handler.h"
+
+#include "base/memory/singleton.h"
+
+// TODO(sriramsr): Implement for other platforms.
+// Empty implementation for other platforms.
+void KeyboardHookHandler::Register(views::Widget* widget) {
+}
+
+void KeyboardHookHandler::Deregister(views::Widget* widget) {
+}
+
+// static
+KeyboardHookHandler* KeyboardHookHandler::GetInstance() {
+  return Singleton<KeyboardHookHandler,
+                   DefaultSingletonTraits<KeyboardHookHandler>>::get();
+}