cros: Clean up TrayBluetoothHelper todos

ash/common/system/chromeos/bluetooth/tray_bluetooth_helper.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ASH_COMMON_SYSTEM_CHROMEOS_BLUETOOTH_TRAY_BLUETOOTH_HELPER_H_
 #define ASH_COMMON_SYSTEM_CHROMEOS_BLUETOOTH_TRAY_BLUETOOTH_HELPER_H_
 
 #include <memory>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "device/bluetooth/bluetooth_adapter.h"
 
 namespace device {
 class BluetoothDiscoverySession;
 }
 
 namespace ash {
 
-// TODO(jamescook): Convert TrayBlueooth to use device::BluetoothDevice and
-// delete this. http://crbug.com/660043
+// Cached info from device::BluetoothDevice used for display in the UI.
+// Exists because it is not safe to cache pointers to device::BluetoothDevice
+// instances.
 struct ASH_EXPORT BluetoothDeviceInfo {

[James Cook, 2017/03/21 23:35:35]

It's possible this struct could be eliminated by making TrayBluetooth store
lists of device addresses instead of lists of this struct. However, the UI would
have to look up the device info from the adapter every time it does something.
I'm concerned that there may be cases where the UI transiently needs to display
a device that just disconnected from the adapter. Also, there are no tests of
TrayBluetooth. So I don't think this is worth "fixing".

[msw, 2017/03/21 23:48:41]

Acknowledged.

   BluetoothDeviceInfo();
   BluetoothDeviceInfo(const BluetoothDeviceInfo& other);
   ~BluetoothDeviceInfo();
 
   std::string address;
   base::string16 display_name;
   bool connected;
   bool connecting;
   bool paired;
   device::BluetoothDeviceType device_type;
@@ skipping 12 matching lines @@
   ~TrayBluetoothHelper() override;
 
   // Initializes and gets the adapter asynchronously.
   void Initialize();
 
   // Completes initialization after the Bluetooth adapter is ready.
   void InitializeOnAdapterReady(
       scoped_refptr<device::BluetoothAdapter> adapter);
 
   // Returns a list of available bluetooth devices.
-  // TODO(jamescook): Just return the list.
-  void GetAvailableBluetoothDevices(std::vector<BluetoothDeviceInfo>* list);
+  BluetoothDeviceList GetAvailableBluetoothDevices() const;
 
   // Requests bluetooth start discovering devices, which happens asynchronously.
   void StartBluetoothDiscovering();
 
   // Requests bluetooth stop discovering devices.
   void StopBluetoothDiscovering();
 
   // Connect to a specific bluetooth device.
   void ConnectToBluetoothDevice(const std::string& address);
 
@@ skipping 34 matching lines @@
 
   // Object could be deleted during a prolonged Bluetooth operation.
   base::WeakPtrFactory<TrayBluetoothHelper> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayBluetoothHelper);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_CHROMEOS_BLUETOOTH_TRAY_BLUETOOTH_HELPER_H_