Bug 453321 - Convenient field access for MITuple/MIResultRecord

Change-Id: Id43f2cb9b52743792fc7f9ce40d16914d8e257b4
Signed-off-by: Vladimir Prus <vladimir@codesourcery.com>
Reviewed-on: https://git.eclipse.org/r/37090
Reviewed-by: Marc Khouzam <marc.khouzam@ericsson.com>