ash: Add a bluetooth entry in the uber tray.

ash/system/tray/system_tray.cc

Index: ash/system/tray/system_tray.cc
diff --git a/ash/system/tray/system_tray.cc b/ash/system/tray/system_tray.cc
index c80726b38c0929cd91b8766387cc4689c78fc2ba..c082fa10021411e79725094f4d7574195a97dc34 100644
--- a/ash/system/tray/system_tray.cc
+++ b/ash/system/tray/system_tray.cc
@@ -376,6 +376,13 @@ NetworkIconInfo::NetworkIconInfo()
 NetworkIconInfo::~NetworkIconInfo() {
 }
 
+BluetoothDeviceInfo::BluetoothDeviceInfo()
+    : connected(false) {
+}
+
+BluetoothDeviceInfo::~BluetoothDeviceInfo() {
+}
+
 IMEInfo::IMEInfo()
     : selected(false) {
 }
@@ -387,6 +394,7 @@ SystemTray::SystemTray()
     : items_(),
       accessibility_observer_(NULL),
       audio_observer_(NULL),
+      bluetooth_observer_(NULL),
       brightness_observer_(NULL),
       caps_lock_observer_(NULL),
       clock_observer_(NULL),