Make Herald less ambitious about resolving repositories for revisions
Summary:
Fixes T4636. If a user manually deletes a "repository" setting from a revision, Herald attempts to resolve it. Instead, Herald should now just trust Differential. Generally, the new logic is:
- When diffs are created, figure out repository information.
- When revisions are updated, copy info from diffs.
- Everywhere else, just trust the revision field.
Test Plan:
- Created revisions.
- Used Herald to dry-run revisions before and after a manual edit to remove the repository setting.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T4636
Differential Revision: https://secure.phabricator.com/D8576