Revert 109960 - Send WM_DEVICECHANGE message through SystemMonitor

WM_DEVICECHANGE is sent when there's been a change to devices or the computer;
specifically when a USB device is connected or disconnected. This is intended
for use in support of Gamepads for more performant polling and
connect/disconnect testing. Currently only on Windows, though seems reasonable
to add for other platforms in the future.

BUG=79050


Review URL: http://codereview.chromium.org/8523021

TBR=scottmg@chromium.org
Review URL: http://codereview.chromium.org/8528044

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@109979 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 3 insertions, 20 deletions

diff --git a/base/system_monitor/system_monitor.h b/base/system_monitor/system_monitor.h
index 7684523..c779994 100644
--- a/base/system_monitor/system_monitor.h
+++ b/base/system_monitor/system_monitor.h
@@ -90,26 +90,15 @@ class BASE_EXPORT SystemMonitor {
     virtual ~PowerObserver() {}
   };
 
-  class BASE_EXPORT DevicesChangedObserver {
-   public:
-    // Notification that the devices connected to the system have changed.
-    virtual void OnDevicesChanged() {}
-
-   protected:
-    virtual ~DevicesChangedObserver() {}
-  };
-
   // Add a new observer.
   // Can be called from any thread.
   // Must not be called from within a notification callback.
-  void AddPowerObserver(PowerObserver* obs);
-  void AddDevicesChangedObserver(DevicesChangedObserver* obs);
+  void AddObserver(PowerObserver* obs);
 
   // Remove an existing observer.
   // Can be called from any thread.
   // Must not be called from within a notification callback.
-  void RemovePowerObserver(PowerObserver* obs);
-  void RemoveDevicesChangedObserver(DevicesChangedObserver* obs);
+  void RemoveObserver(PowerObserver* obs);
 
 #if defined(OS_WIN)
   // Windows-specific handling of a WM_POWERBROADCAST message.
@@ -121,9 +110,6 @@ class BASE_EXPORT SystemMonitor {
   // Cross-platform handling of a power event.
   void ProcessPowerMessage(PowerEvent event_id);
 
-  // Cross-platform handling of a device change event.
-  void ProcessDevicesChanged();
-
  private:
 #if defined(OS_MACOSX)
   void PlatformInit();
@@ -140,14 +126,11 @@ class BASE_EXPORT SystemMonitor {
   void BatteryCheck();
 
   // Functions to trigger notifications.
-  void NotifyDevicesChanged();
   void NotifyPowerStateChange();
   void NotifySuspend();
   void NotifyResume();
 
-  scoped_refptr<ObserverListThreadSafe<PowerObserver> > power_observer_list_;
-  scoped_refptr<ObserverListThreadSafe<DevicesChangedObserver> >
-      devices_changed_observer_list_;
+  scoped_refptr<ObserverListThreadSafe<PowerObserver> > observer_list_;
   bool battery_in_use_;
   bool suspended_;