Add Media device notification to SystemMonitor and Mac impl

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 28fc70bf2b42a1dd21dc04880ac17efec4ea55ab..482142f8ff11c71ebc2a985974d5090097cf82c8 100644
--- a/base/system_monitor/system_monitor.cc
+++ b/base/system_monitor/system_monitor.cc
@@ -83,6 +83,16 @@ void SystemMonitor::ProcessDevicesChanged() {
   NotifyDevicesChanged();
 }
 
+void SystemMonitor::ProcessMediaDeviceAttached(const DeviceIdType& id,
+                                               const std::string& name,
+                                               const FilePath& path) {
+  NotifyMediaDeviceAttached(id, name, path);
+}
+
+void SystemMonitor::ProcessMediaDeviceDetached(const DeviceIdType& id) {
+  NotifyMediaDeviceDetached(id);
+}
+
 void SystemMonitor::AddPowerObserver(PowerObserver* obs) {
   power_observer_list_->AddObserver(obs);
 }
@@ -105,6 +115,20 @@ void SystemMonitor::NotifyDevicesChanged() {
     &DevicesChangedObserver::OnDevicesChanged);
 }
 
+void SystemMonitor::NotifyMediaDeviceAttached(const DeviceIdType& id,
+                                              const std::string& name,
+                                              const FilePath& path) {
+  DVLOG(1) << "MediaDeviceAttached with name " << name << " and id " << id;
+  devices_changed_observer_list_->Notify(
+    &DevicesChangedObserver::OnMediaDeviceAttached, id, name, path);
+}
+
+void SystemMonitor::NotifyMediaDeviceDetached(const DeviceIdType& id) {
+  DVLOG(1) << "MediaDeviceDetached for id " << id;
+  devices_changed_observer_list_->Notify(
+    &DevicesChangedObserver::OnMediaDeviceDetached, id);
+}
+
 void SystemMonitor::NotifyPowerStateChange() {
   DVLOG(1) << "PowerStateChange: " << (BatteryPower() ? "On" : "Off")
            << " battery";