[Refactor] Slash-n-Burn Poll BuiltIn XBlock

[irfanuddinahmad]

See parent epic: openedx/openedx-platform#37819

---

Rollout Position

Step 1 of 8 — Smallest footprint (~380 LOC), no external integrations, minimal risk. Start here to validate the removal workflow end-to-end.

---

Block Details

Toggle	USE_EXTRACTED_POLL_QUESTION_BLOCK in openedx/envs/common.py
Shim class	_BuiltInPollBlock in xmodule/poll_block.py
Entrypoint	poll_question = "xmodule.poll_block:PollBlock" in pyproject.toml

---

Checklist

Pre-condition

• Review PRs merged into the built-in Poll XBlock code in edx-platform after the extraction work was done — port any bug fixes or improvements to xblocks-contrib if not already there.

Steps (single PR)

• Remove the toggle — delete USE_EXTRACTED_POLL_QUESTION_BLOCK from openedx/envs/common.py and all usages.
• Remove the shim — delete _BuiltInPollBlock class and the from xblocks_contrib.poll import PollBlock as _ExtractedPollBlock import from xmodule/poll_block.py.
• Remove the entrypoint — delete poll_question = "xmodule.poll_block:PollBlock" from pyproject.toml.
• Remove remaining assets:
  • xmodule/poll_block.py (Python class)
  • xmodule/js/src/poll/ (JavaScript)
  • lms/templates/poll.html (template)
  • xmodule/static/css-builtin-blocks/PollBlockDisplay.css (CSS)
  • Webpack entries PollBlockDisplay / PollBlockEditor in webpack.builtinblocks.config.js
• Run smoke tests on the extracted Poll block to verify nothing is broken.

[irfanuddinahmad]

Implementation PR: openedx/openedx-platform#38744