Revert of Revert of [Easy Unlock] Port the BluetoothConnectionFinder class to native code.

components/proximity_auth/bluetooth_connection_finder.h

Index: components/proximity_auth/bluetooth_connection_finder.h
diff --git a/components/proximity_auth/bluetooth_connection_finder.h b/components/proximity_auth/bluetooth_connection_finder.h
new file mode 100644
index 0000000000000000000000000000000000000000..8de83b7707b62b59b01013bb2db89fd20e2a8afa
--- /dev/null
+++ b/components/proximity_auth/bluetooth_connection_finder.h
@@ -0,0 +1,108 @@
+// Copyright 2014 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 COMPONENTS_PROXIMITY_AUTH_BLUETOOTH_CONNECTION_FINDER_H
+#define COMPONENTS_PROXIMITY_AUTH_BLUETOOTH_CONNECTION_FINDER_H
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/time/time.h"
+#include "components/proximity_auth/connection_finder.h"
+#include "components/proximity_auth/connection_observer.h"
+#include "components/proximity_auth/remote_device.h"
+#include "device/bluetooth/bluetooth_adapter.h"
+#include "device/bluetooth/bluetooth_uuid.h"
+
+namespace proximity_auth {
+
+class BluetoothConnection;
+
+// This ConnectionFinder implementation tries to find a Bluetooth connection to
+// the remote device by polling at a fixed interval.
+class BluetoothConnectionFinder : public ConnectionFinder,
+                                  public ConnectionObserver,
+                                  public device::BluetoothAdapter::Observer {
+ public:
+  BluetoothConnectionFinder(const RemoteDevice& remote_device,
+                            const device::BluetoothUUID& uuid,
+                            const base::TimeDelta& polling_interval);
+  virtual ~BluetoothConnectionFinder();
+
+  // ConnectionFinder:
+  virtual void Find(const ConnectionCallback& connection_callback) override;
+
+ protected:
+  // Exposed for mocking out the connection in tests.
+  virtual scoped_ptr<Connection> CreateConnection();
+
+  // BluetoothAdapter::Observer:
+  virtual void AdapterPresentChanged(device::BluetoothAdapter* adapter,
+                                     bool present) override;
+  virtual void AdapterPoweredChanged(device::BluetoothAdapter* adapter,
+                                     bool powered) override;
+
+ private:
+  // Returns true iff the Bluetooth adapter is ready to make connections.
+  bool IsReadyToPoll();
+
+  // Attempts to connect to the |remote_device_| if the system is ready for
+  // another iteration of polling.
+  void PollIfReady();
+
+  // Wrapper around |PollIfReady()| that can be posted as a delayed task.
+  void DelayedPollIfReady();
+
+  // Unregisters |this| instance as an observer from all objects that it might
+  // have registered with.
+  void UnregisterAsObserver();
+
+  // Callback to be called when the Bluetooth adapter is initialized.
+  void OnAdapterInitialized(scoped_refptr<device::BluetoothAdapter> adapter);
+
+  // ConnectionObserver:
+  virtual void OnConnectionStatusChanged(
+      const Connection& connection,
+      Connection::Status old_status,
+      Connection::Status new_status) override;
+
+  // The remote device to connect to.
+  const RemoteDevice remote_device_;
+
+  // The UUID of the service on the remote device.
+  const device::BluetoothUUID uuid_;
+
+  // The time to wait between polling attempts.
+  const base::TimeDelta polling_interval_;
+
+  // Records the time at which the finder began searching for connections.
+  base::TimeTicks start_time_;
+
+  // The callback that should be called upon a successful connection.
+  ConnectionCallback connection_callback_;
+
+  // The Bluetooth adapter over which the Bluetooth connection will be made.
+  scoped_refptr<device::BluetoothAdapter> adapter_;
+
+  // The Bluetooth connection that will be opened.
+  scoped_ptr<Connection> connection_;
+
+  // Whether there is currently a polling task scheduled.
+  bool has_delayed_poll_scheduled_;
+
+  // Used to schedule everything else.
+  base::WeakPtrFactory<BluetoothConnectionFinder> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(BluetoothConnectionFinder);
+};
+
+// TODO(isherman): Make sure to wire up the controller to listen for screen lock
+// state change events, and create or destroy the connection finder as
+// appropriate.
+
+}  // namespace proximity_auth
+
+#endif  // COMPONENTS_PROXIMITY_AUTH_BLUETOOTH_CONNECTION_FINDER_H