Use physical_resource_name to generate the resource ID

The SwiftSignalHandle URL can be too long for the database column,
resulting in an unhandled exception and failed stack.

Use the SwiftSignalHandle's physical_resource_name() method to generate
the resource ID and use FnGetRefId to fetch the handle URL instead.

Change-Id: Iee5fc684b1f2f64ed543022a9e51612c1f80bb1e
Closes-Bug: #1398927
Merge "Use physical_resource_name to generate the resource ID"