Forwarded v1 libraries do not show new content updates

[ormsbee]

Impact: This will cause migrated libraries to no longer be synced to the courses that use them, negating a lot of the value of the migration process.

Steps:

1. As a non-global staff user (just a course creator for an org), create a legacy library with two problems in it.
2. Create a course and add the legacy library randomized content block.
3. Publish the course.
4. Migrate the v1 library into an existing v2 library.
5. The randomized content block in the course will now tell you that you have to update your references. Do this.
6. Make changes to the content of one of the migrated problems in its new location in the v2 library, and publish those changes.
7. The content update does not show up in the course under the list of content updates from the library. The v2 library itself does not show up. It's as if the course lost the reference to the v2 library entirely.

The data seems to look right to me on the model forwarding backend, but the modulestore references look wrong to me. Specifically, I see this OLX:

<library_content is_migrated_to_v2="true" source_library_id="library-v1:Axim+OldLibForRefTesting" source_library_version="694962eaa62a3739836366a0">
  <problem url_name="d2ce6054010e911c5c16"/>
  <problem url_name="214a499ff852bcc64145"/>
</library_content>

But the upstream values are missing for the problems, e.g.:

<problem upstream=""><div>Q1 Text here</div>
<numericalresponse answer="10"><responseparam type="tolerance" default="5"/><formulaequationinput/></numericalresponse>
</problem>

[ormsbee]

FYI @kdmccormick: I'm looking into this, but either way the release is delayed until after everyone gets back from break (either Jan 8 or 15), so it's not something to stress about over the holidays.

[ormsbee]

This reproduces locally on master.