Change "Add Device" button to "Manage Devices" on ash tray bluetooth page.

ash/system/tray/system_tray_delegate.h

Index: ash/system/tray/system_tray_delegate.h
diff --git a/ash/system/tray/system_tray_delegate.h b/ash/system/tray/system_tray_delegate.h
index ee60831091e4a8e001ca2a1fe031e985dcbc0271..45b0c71c8cd56f5b008a2d50f33251e396c50d4d 100644
--- a/ash/system/tray/system_tray_delegate.h
+++ b/ash/system/tray/system_tray_delegate.h
@@ -253,8 +253,8 @@ class SystemTrayDelegate {
   // Sends a connect request for the network specified by |network_id|.
   virtual void ConnectToNetwork(const std::string& network_id) = 0;
 
-  // Shows UI to add a new bluetooth device.
-  virtual void AddBluetoothDevice() = 0;
+  // Shows UI to manage bluetooth devices.
+  virtual void ManageBluetoothDevices() = 0;
 
   // Toggles bluetooth.
   virtual void ToggleBluetooth() = 0;