This means that all reference nodes are treated as comparable
in the diff (provided they are in the same group) so will
not show up in the article diff if their index changes.
Changes to the reference list are already handled separately
by the visual diff.
Bug: T170235
Change-Id: I8c26686d7b2fe3bf91af7d4dcab1caf3247dbe47
* Add it to CE HTML, for compatibility with site styles.
* Add it to DM HTML of newly created references only. Existing
references just use whatever classes we got from Parsoid, to avoid
unnecessary DOM changes and dirty diffs.
Bug: T265930
Depends-On: I61a2132f3876e2d9567d985358f51eb51c479813
Change-Id: I9d6856f03071c09617b8ae7db938135a3e30fe8e
