Send WM_DEVICECHANGE message through SystemMonitor

base/system_monitor/system_monitor.cc

Index: base/system_monitor/system_monitor.cc
diff --git a/base/system_monitor/system_monitor.cc b/base/system_monitor/system_monitor.cc
index 5131fbf124c7689aeecba0783c727e9b5db89664..ed6a1c76b62687996a90f3b65e8dfc4536a5382f 100644
--- a/base/system_monitor/system_monitor.cc
+++ b/base/system_monitor/system_monitor.cc
@@ -19,7 +19,9 @@ static int kDelayedBatteryCheckMs = 10 * 1000;
 #endif  // defined(ENABLE_BATTERY_MONITORING)
 
 SystemMonitor::SystemMonitor()
-    : observer_list_(new ObserverListThreadSafe<PowerObserver>()),
+    : power_observer_list_(new ObserverListThreadSafe<PowerObserver>()),
+      device_change_observer_list_(
+          new ObserverListThreadSafe<DeviceChangeObserver>()),
       battery_in_use_(false),
       suspended_(false) {
   DCHECK(!g_system_monitor);
@@ -77,28 +79,46 @@ void SystemMonitor::ProcessPowerMessage(PowerEvent event_id) {
   }
 }
 
+void SystemMonitor::ProcessDeviceChange() {
+  NotifyDeviceChange();
+}
+
 void SystemMonitor::AddObserver(PowerObserver* obs) {
-  observer_list_->AddObserver(obs);
+  power_observer_list_->AddObserver(obs);
 }
 
 void SystemMonitor::RemoveObserver(PowerObserver* obs) {
-  observer_list_->RemoveObserver(obs);
+  power_observer_list_->RemoveObserver(obs);
+}
+
+void SystemMonitor::AddObserver(DeviceChangeObserver* obs) {
+  device_change_observer_list_->AddObserver(obs);
+}
+
+void SystemMonitor::RemoveObserver(DeviceChangeObserver* obs) {
+  device_change_observer_list_->RemoveObserver(obs);
+}
+
+void SystemMonitor::NotifyDeviceChange() {
+  DVLOG(1) << "DeviceChange";
+  device_change_observer_list_->Notify(&DeviceChangeObserver::OnDeviceChange);
 }
 
 void SystemMonitor::NotifyPowerStateChange() {
   DVLOG(1) << "PowerStateChange: " << (BatteryPower() ? "On" : "Off")
            << " battery";
-  observer_list_->Notify(&PowerObserver::OnPowerStateChange, BatteryPower());
+  power_observer_list_->Notify(&PowerObserver::OnPowerStateChange,
+                               BatteryPower());
 }
 
 void SystemMonitor::NotifySuspend() {
   DVLOG(1) << "Power Suspending";
-  observer_list_->Notify(&PowerObserver::OnSuspend);
+  power_observer_list_->Notify(&PowerObserver::OnSuspend);
 }
 
 void SystemMonitor::NotifyResume() {
   DVLOG(1) << "Power Resuming";
-  observer_list_->Notify(&PowerObserver::OnResume);
+  power_observer_list_->Notify(&PowerObserver::OnResume);
 }
 
 void SystemMonitor::BatteryCheck() {