BUG-997: Fix URLSchemaContextResolver

The new URLSchemaContextResolver contained a few bugs which prevented it
from working correctly. Fix patches fixes it up.

Change-Id: Ica34f4b8f9e2bb50fe5107f35f987d2bf0891a14
Signed-off-by: Robert Varga <rovarga@cisco.com>
Merge "BUG-997: Fix URLSchemaContextResolver"