Convert DeviceManagerDelegate to PermissionProvider mojo interface.

device/devices_app/usb/public/interfaces/permission_provider.mojom

Index: device/devices_app/usb/public/interfaces/permission_provider.mojom
diff --git a/device/devices_app/usb/public/interfaces/permission_provider.mojom b/device/devices_app/usb/public/interfaces/permission_provider.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..90fd0ea4bab4b16657ba49515c77eabca82d6da8
--- /dev/null
+++ b/device/devices_app/usb/public/interfaces/permission_provider.mojom
@@ -0,0 +1,14 @@
+// Copyright 2015 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.usb;
+
+import "device.mojom";
+
+interface PermissionProvider {
+  // Filters a set of |requested_guids| down to the set of |allowed_guids| that
+  // should be accessible to clients of the DeviceManager instance.
+  HasDevicePermission(array<string> requested_guids)
+      => (array<string> allowed_guids);
+};