Add bluetooth device type icons on MD system tray.

ash/common/system/tray/system_tray_delegate.h

Index: ash/common/system/tray/system_tray_delegate.h
diff --git a/ash/common/system/tray/system_tray_delegate.h b/ash/common/system/tray/system_tray_delegate.h
index 9ec8238f508bdfba076488d0b6bbe1df7375048c..61ab2b886b70ab47aa0dee6ed9658b6ddf92f7a1 100644
--- a/ash/common/system/tray/system_tray_delegate.h
+++ b/ash/common/system/tray/system_tray_delegate.h
@@ -55,10 +55,12 @@ struct ASH_EXPORT NetworkIconInfo {
 
 struct ASH_EXPORT BluetoothDeviceInfo {
   BluetoothDeviceInfo();
+  BluetoothDeviceInfo(const BluetoothDeviceInfo& other);
   ~BluetoothDeviceInfo();
 
   std::string address;
   base::string16 display_name;
+  gfx::ImageSkia icon_image;
   bool connected;
   bool connecting;
   bool paired;