Declarative schema changer operation names and their field names are mildly inconsistent. For instance we have a pattern where index state changing ops are named MakeBackfilledIndexMerging, MakeBackfillingIndexDeleteOnly, etc. but we also have MakeAddedIndexDeleteAndWriteOnly which doesn't conform to the pattern. As far as fields are concerned we have a mix of DescID, DescriptorID etc.

None of this matters in any other way than: this stuff shows up in EXPLAIN (DDL) output. Let's make it consistent in time for this release. It shouldn't be hard or take long, but will result in noisy test changes.

Jira issue: CRDB-17746