device/bluetooth: Implement BluetoothGattConnection on Chrome OS.

chromeos/dbus/fake_bluetooth_device_client.cc

Index: chromeos/dbus/fake_bluetooth_device_client.cc
diff --git a/chromeos/dbus/fake_bluetooth_device_client.cc b/chromeos/dbus/fake_bluetooth_device_client.cc
index 2dd5aaea70e64f4f77cf7c374829b0e723dc14bf..87b6591d9315fdfbf17977704b8ef125e4414c1b 100644
--- a/chromeos/dbus/fake_bluetooth_device_client.cc
+++ b/chromeos/dbus/fake_bluetooth_device_client.cc
@@ -293,7 +293,8 @@ void FakeBluetoothDeviceClient::Connect(
   }
 
   if (properties->paired.value() != true &&
-      object_path != dbus::ObjectPath(kConnectUnpairablePath)) {
+      object_path != dbus::ObjectPath(kConnectUnpairablePath) &&
+      object_path != dbus::ObjectPath(kLowEnergyPath)) {
     // Must be paired.
     error_callback.Run(bluetooth_device::kErrorFailed, "Not paired");
     return;