Check USB device path access when prompting users to select a device.

chromeos/dbus/permission_broker_client.h

Index: chromeos/dbus/permission_broker_client.h
diff --git a/chromeos/dbus/permission_broker_client.h b/chromeos/dbus/permission_broker_client.h
index aa14757418bb4f0ce98533ffb869da33899e02f1..4dfe4fa5035abd85d14070f3a915934a4332bc12 100644
--- a/chromeos/dbus/permission_broker_client.h
+++ b/chromeos/dbus/permission_broker_client.h
@@ -36,6 +36,13 @@ class CHROMEOS_EXPORT PermissionBrokerClient : public DBusClient {
 
   static PermissionBrokerClient* Create();
 
+  // CheckPathAccess requests a hint from the permission broker about whether
+  // a later call to RequestPathAccess will be successful. It presumes that
+  // the |interface_id| value passed to RequestPathAccess will be
+  // UsbDevicePermissionsData::ANY_INTERFACE).
+  virtual void CheckPathAccess(const std::string& path,
+                               const ResultCallback& callback) = 0;
+
   // RequestPathAccess requests access to a single device node identified by
   // |path|. If |interface_id| value is passed (different than
   // UsbDevicePermissionData::ANY_INTERFACE), the request will check if a