Summary:
- When adding records, negative rowIds may now be specified. They'll be replaced by proper IDs.
- If these negative IDs are used in Reference columns in subsequent actions in
the same bundle of UserActions, they get replaced with the proper rowIds.
- Use this to sync ACLResources and ACLRules from UI in a single batch of UserActions.
- Resolve the TODOs in GranularAccess test, to no longer need to guess resource rowIds.
Test Plan: Added a python unittest for mapping IDs; updated browser tests.
Reviewers: paulfitz
Reviewed By: paulfitz
Differential Revision: https://phab.getgrist.com/D2691
