Add a SyncJobStatus result callback amid Sync retries

[ndegwamartin]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes google#2049

Description
Clear and concise code change description.

Alternative(s) considered
We can also have the method be Abstract and let the user app implement the logic it requires

Type
Choose one: (Bug fix | Feature | Documentation | Testing | Code health | Builds | Releases | Other)

Screenshots (if applicable)

Checklist

• I have read and acknowledged the Code of conduct.
• I have read the Contributing page.
• I have signed the Google Individual CLA, or I am covered by my company's Corporate CLA.
• I have discussed my proposed solution with code owners in the linked issue(s) and we have agreed upon the general approach.
• I have run ./gradlew spotlessApply and ./gradlew spotlessCheck to check my code follows the style guide of this project.
• I have run ./gradlew check and ./gradlew connectedCheck to test my changes locally.
• I have built and run the demo app(s) to verify my change fixes the issue and/or does not break the demo app(s).