tree 743aa8c4d3249cc8ec04bd4ce561e81823ba5bcf
parent 48fc322e6aa7a015966b3712110546ed73622be9
author Dave Borowitz <dborowitz@google.com> 1421342780 -0500
committer Dave Borowitz <dborowitz@google.com> 1421418710 -0500

Fix all ChangeFields to properly handle null values

Many ChangeData methods can return null values, typically indicating
a change is corrupt. Handle these gracefully within ChangeFields by
just not emitting the field values.

Fix a few ChangeData methods to return null that were previously
throwing exceptions, for consistency.

Testing this is hard. We get a little coverage for missing patch sets
by trying to reindex the changes in CheckIT; unfortunately this won't
work for testing a missing change.

Change-Id: Ia9b2722bb07d0025ca45631648ef060ff5b4f117