Use helper DeviceChangeHandler to call mousecontrol/tpcontrol whenever a device is attached.

chrome/browser/chromeos/system/device_change_handler.cc

+// 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.
+
+#include "chrome/browser/chromeos/system/device_change_handler.h"
+
+#include "base/prefs/pref_service.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/chromeos/system/input_device_settings.h"
+#include "chrome/browser/profiles/profile_manager.h"
+#include "chrome/common/pref_names.h"
+
+namespace chromeos {
+namespace system {
+
+DeviceChangeHandler::DeviceChangeHandler()
+    : pointer_device_observer_(new PointerDeviceObserver) {
+  pointer_device_observer_->AddObserver(this);
+  pointer_device_observer_->Init();
+}
+
+DeviceChangeHandler::~DeviceChangeHandler() {

[xiyuan, 2013/05/23 21:40:42]

nit: Do we need to RemoveObserver(this)?

[achuithb, 2013/05/23 21:51:42]

Better to be explicit, so I added it. Done.

+}
+
+// When we detect a touchpad is attached, apply touchpad settings of the last
+// used profile.
+void DeviceChangeHandler::TouchpadExists(bool exists) {
+  if (!exists)
+    return;
+
+  PrefService* prefs =
+      g_browser_process->profile_manager()->GetLastUsedProfile()->GetPrefs();
+
+  const bool tap_to_click = prefs->GetBoolean(prefs::kTapToClickEnabled);
+  system::touchpad_settings::SetTapToClick(tap_to_click);
+
+  const bool tap_dragging = prefs->GetBoolean(prefs::kTapDraggingEnabled);
+  system::touchpad_settings::SetTapDragging(tap_dragging);
+
+  const bool three_finger_click =
+      prefs->GetBoolean(prefs::kEnableTouchpadThreeFingerClick);
+  system::touchpad_settings::SetThreeFingerClick(three_finger_click);
+
+  const bool three_finger_swipe =
+      prefs->GetBoolean(prefs::kEnableTouchpadThreeFingerSwipe);
+  system::touchpad_settings::SetThreeFingerSwipe(three_finger_swipe);
+
+  const int sensitivity = prefs->GetInteger(prefs::kTouchpadSensitivity);
+  system::touchpad_settings::SetSensitivity(sensitivity);
+}
+
+// When we detect a mouse is attached, apply mouse settings of the last
+// used profile.
+void DeviceChangeHandler::MouseExists(bool exists) {
+  if (!exists)
+    return;
+
+  PrefService* prefs =
+      g_browser_process->profile_manager()->GetLastUsedProfile()->GetPrefs();
+
+  const int sensitivity = prefs->GetInteger(prefs::kMouseSensitivity);
+  system::mouse_settings::SetSensitivity(sensitivity);
+
+  const bool primary_button_right =
+      prefs->GetBoolean(prefs::kPrimaryMouseButtonRight);
+  system::mouse_settings::SetPrimaryButtonRight(primary_button_right);
+}
+
+}  // namespace system
+}  // namespace chromeos
+