Isolated FS for media devices.

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 6db1db582646ad2b8d1b0b39cc7c0ebeb7a136b4..7c0f58e3e69ec8b216b495a9cd45e10213536d45 100644
--- a/base/system_monitor/system_monitor.cc
+++ b/base/system_monitor/system_monitor.cc
@@ -104,9 +104,11 @@ void SystemMonitor::ProcessMediaDeviceAttached(
 
 void SystemMonitor::ProcessMediaDeviceDetached(const std::string& id) {
   MediaDeviceMap::iterator it = media_device_map_.find(id);
-  if (it != media_device_map_.end())
-    media_device_map_.erase(it);
-  NotifyMediaDeviceDetached(id);
+  if (it == media_device_map_.end())
+    return;
+
+  NotifyMediaDeviceDetached(id, it->second.location);
+  media_device_map_.erase(it);
 }
 
 std::vector<SystemMonitor::MediaDeviceInfo>
@@ -153,10 +155,12 @@ void SystemMonitor::NotifyMediaDeviceAttached(
     &DevicesChangedObserver::OnMediaDeviceAttached, id, name, type, location);
 }
 
-void SystemMonitor::NotifyMediaDeviceDetached(const std::string& id) {
+void SystemMonitor::NotifyMediaDeviceDetached(
+    const std::string& id,
+    const FilePath::StringType& location) {
   DVLOG(1) << "MediaDeviceDetached for id " << id;
   devices_changed_observer_list_->Notify(
-    &DevicesChangedObserver::OnMediaDeviceDetached, id);
+    &DevicesChangedObserver::OnMediaDeviceDetached, id, location);
 }
 
 void SystemMonitor::NotifyPowerStateChange() {