BUG-981: make some methods static and non-public

These two methods can be made static, allowing for further code
reorganization. Also renames log to LOG to comply with standards.

Change-Id: I63abecfbb3d2fc891b6f37123cf503e8d20dc289
Signed-off-by: Robert Varga <rovarga@cisco.com>
(cherry picked from commit 0e8d68c64289e405590d01bd36d484a7117c83fb)
Signed-off-by: Robert Varga <rovarga@cisco.com>
BUG-981: force callers to handle exceptions

This patch makes sure all the callsites acknowledge that the
transformer generator may fail. Also introduces proper chaining so we do
not lose information.

Change-Id: Ifce672b52a4f9d07104778f4e5060f51804747cc
Signed-off-by: Robert Varga <rovarga@cisco.com>
(cherry picked from commit 03180983f08c3f353a75f5eb27cbdf8d0f478ccf)
Signed-off-by: Robert Varga <rovarga@cisco.com>