device/bluetooth/bluez: add discoverable timeout adapter property

device/bluetooth/bluetooth_adapter.h

 // Copyright (c) 2012 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_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_ADAPTER_H_
 
 #include <stdint.h>
 
 #include <list>
@@ skipping 292 matching lines @@
   virtual bool IsDiscoverable() const = 0;
 
   // Requests that the adapter change its discoverability state. If
   // |discoverable| is true, then it will be discoverable by other Bluetooth
   // devices. On successfully changing the adapter's discoverability, |callback|
   // will be called. On failure, |error_callback| will be called.
   virtual void SetDiscoverable(bool discoverable,
                                const base::Closure& callback,
                                const ErrorCallback& error_callback) = 0;
 
+#if defined(OS_CHROMEOS) || defined(OS_LINUX)
+  // Returns the timeout after which the adapter exits discoverable mode in
+  // seconds, or zero if the adapter is always discoverable.
+  virtual uint32_t GetDiscoverableTimeout() const = 0;

[rkc, 2016/06/23 23:53:05]

Is this something other platforms may need or is it something we are doing
exclusively for compatibility with ARC++?

+#endif
+
   // Indicates whether the adapter is currently discovering new devices.
   virtual bool IsDiscovering() const = 0;
 
   // Requests the adapter to start a new discovery session. On success, a new
   // instance of BluetoothDiscoverySession will be returned to the caller via
   // |callback| and the adapter will be discovering nearby Bluetooth devices.
   // The returned BluetoothDiscoverySession is owned by the caller and it's the
   // owner's responsibility to properly clean it up and stop the session when
   // device discovery is no longer needed.
   //
@@ skipping 275 matching lines @@
   std::set<BluetoothDiscoverySession*> discovery_sessions_;
 
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<BluetoothAdapter> weak_ptr_factory_;
 };
 
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_ADAPTER_H_