bluetooth: macOS: Adding explicit function to log NSError

device/bluetooth/bluetooth_adapter_mac.h

 // Copyright 2013 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 DEVICE_BLUETOOTH_BLUETOOTH_ADAPTER_MAC_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_ADAPTER_MAC_H_
 
 #include <IOKit/IOReturn.h>
 
 #include <memory>
@@ skipping 35 matching lines @@
  public:
   static base::WeakPtr<BluetoothAdapterMac> CreateAdapter();
   static base::WeakPtr<BluetoothAdapterMac> CreateAdapterForTest(
       std::string name,
       std::string address,
       scoped_refptr<base::SequencedTaskRunner> ui_task_runner);
 
   // Converts CBUUID into BluetoothUUID
   static BluetoothUUID BluetoothUUIDWithCBUUID(CBUUID* UUID);
 
+  // Converts NSError to string for logging.
+  static std::string String(NSError* error);
+
   // BluetoothAdapter overrides:
   std::string GetAddress() const override;
   std::string GetName() const override;
   void SetName(const std::string& name,
                const base::Closure& callback,
                const ErrorCallback& error_callback) override;
   bool IsInitialized() const override;
   bool IsPresent() const override;
   bool IsPowered() const override;
   void SetPowered(bool powered,
@@ skipping 156 matching lines @@
   base::scoped_nsobject<BluetoothLowEnergyCentralManagerDelegate>
       low_energy_central_manager_delegate_;
 
   scoped_refptr<base::SequencedTaskRunner> ui_task_runner_;
 
   base::WeakPtrFactory<BluetoothAdapterMac> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothAdapterMac);
 };
 
-// Stream operator for logging.
-DEVICE_BLUETOOTH_EXPORT std::ostream& operator<<(std::ostream& out,
-                                                 NSError* error);
-
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_ADAPTER_MAC_H_