Web Contents are missing fileEntryId from their Image references' JSON object after upgrade

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.X, 7.1.X, 7.2.X, Master
• Fix Version/s: 7.1.10 DXP FP13, 7.1.X, 7.2.10 DXP FP1, 7.2.X, 7.2.1 CE GA2, Master
• Component/s: Web Content > Web Content Administration
• Labels:
  • INACTIVE
  • ee-ts
  • liferay-fixpack-dxp-1-7210
  • liferay-fixpack-dxp-13-7110
  • pt-upgrade-review
• Branch Version/s:
  7.2.x, 7.1.x
• Backported to Branch:
  Committed
• Fix Priority: 3
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/76198

here are some inconsistencies in the content structures of journal articles that get migrated, compared to the ones that are manually added after the migration.

Reproduction steps:

1. Start a 6.2 portal
2. Create a Web Content structure with an image field and a default template
3. Create a content based on that structure - add an image
4. Upgrade the database to 7.1
5. Create another content based on that structure - again add an image to the image field
6. Compare the contents

Expected: the Image's content JSON has fileEntryId

Actual: the fileEntryId is in the Image elements xml properties