Host fingerprint mojo service within the device service.

services/device/public/interfaces/fingerprint.mojom

Index: services/device/public/interfaces/fingerprint.mojom
diff --git a/services/device/public/interfaces/fingerprint.mojom b/services/device/public/interfaces/fingerprint.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..3180f9c0026c77dba7bfebf3fe6f40cdb591d027
--- /dev/null
+++ b/services/device/public/interfaces/fingerprint.mojom
@@ -0,0 +1,26 @@
+// 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.
+
+module device.mojom;
+
+interface BiodObserver{

[blundell, 2017/02/06 14:52:43]

These interfaces and methods should have comments explaining their usage. 

[xiaoyinh(OOO Sep 11-29), 2017/02/22 00:04:50]

Done.

+  OnRestarted();
+  OnScanned(uint32 scan_result, bool is_complete);
+  OnAttempt(uint32 scan_result, array<string> recognized_user_ids);
+  OnFailure();
+};
+
+interface Fingerprint {
+  GetFingerprintsList() => (array<string> enrollments);
+  StartEnroll(string user_id, string label);
+  CancelCurrentEnroll();
+  GetLabel(int32 index) => (string label);
+  SetLabel(string label, int32 index);
+  RemoveEnrollment(int32 index);
+  StartAuthentication();
+  EndCurrentAuthentication();
+  DestroyAllEnrollments();
+  AddBiodObserver(BiodObserver observer);
+};
+