🚨 Error: Null promise in layoutCallback

Details
---
**Error report:** [link](http://go/ampe/CNnAtt7Wjeb8Dg)
**First seen:** Feb 9, 2022
**Frequency:** ~ 56,440/day

Stacktrace
---

Error: Null promise in layoutCallback

    at map (src/core/types/object/index.js:172:15)

    at src/utils/log.js:399:6

    at message (src/utils/log.js:321:40)

    at error (extensions/amp-a4a/0.1/amp-a4a.js:1343:14)

    at attemptToRenderCreative (extensions/amp-a4a/0.1/amp-a4a.js:1323:16)

    at layoutCallback (extensions/amp-a4a/0.1/amp-a4a.js:415:37)

    at isInputPending (src/chunk.js:304:37)

    at src/chunk.js:533:2

    at Date (src/chunk.js:408:15)

Notes
---
`@rcebulko` modified `src/core/types/object/index.js:170-179` in [#34367](https://github.com/ampproject/amphtml/pull/34367) (May 14, 2021)
`@rcebulko` modified `src/utils/log.js:399-401` in [#34061](https://github.com/ampproject/amphtml/pull/34061) (Apr 28, 2021)
`@rcebulko` modified `src/utils/log.js:313-323` in [#35461](https://github.com/ampproject/amphtml/pull/35461) (Aug 9, 2021)
`@samouri` modified `extensions/amp-a4a/0.1/amp-a4a.js:1323-1323` in [#30859](https://github.com/ampproject/amphtml/pull/30859) (Oct 30, 2020)
`@powerivq` modified `extensions/amp-a4a/0.1/amp-a4a.js:410-417` in [#37456](https://github.com/ampproject/amphtml/pull/37456) (Jan 29, 2022)
`@kristoferbaxter` modified `src/chunk.js:301-305` in [#30300](https://github.com/ampproject/amphtml/pull/30300) (Sep 23, 2020)
`@cramforce` modified `src/chunk.js:533-537` in [#6460](https://github.com/ampproject/amphtml/pull/6460) (Dec 7, 2016)
`@cramforce` modified `src/chunk.js:408-408` in [#23845](https://github.com/ampproject/amphtml/pull/23845) (Aug 9, 2019)

**Seen in:**
- 02-04 Stable (2210+1)

**Possible assignees:** `@powerivq`, `@rcebulko`

/cc @ampproject/release-on-duty