[Refactor] Slash-n-Burn Video BuiltIn XBlock

[irfanuddinahmad]

See parent epic: openedx/openedx-platform#37819

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Rollout Position

Step 7 of 8 — High complexity (~11K LOC + large asset directory). The Video block has tight CMS integration (transcript handlers, public video sharing), a large xmodule/assets/video/ directory, and two entrypoints to remove (video and videoalpha).

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Block Details

Toggle	USE_EXTRACTED_VIDEO_BLOCK in openedx/envs/common.py
Shim class	_BuiltInVideoBlock in xmodule/video_block/video_block.py
Entrypoints	video = "xmodule.video_block:VideoBlock" and videoalpha = "xmodule.video_block:VideoBlock" in pyproject.toml

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Checklist

Pre-condition

• Review PRs merged into the built-in Video XBlock code in edx-platform after the extraction work was done — port any bug fixes or improvements to xblocks-contrib if not already there.
• Confirm CMS transcript handlers and public video sharing feature are covered by the extracted block.

Steps (single PR)

• Remove the toggle — delete USE_EXTRACTED_VIDEO_BLOCK from openedx/envs/common.py and all usages.
• Remove the shim — delete _BuiltInVideoBlock class and the from xblocks_contrib.video import VideoBlock as _ExtractedVideoBlock import from xmodule/video_block/video_block.py.
• Remove both entrypoints — delete video and videoalpha entries from pyproject.toml.
• Remove remaining assets:
  • xmodule/video_block/ (entire directory: video_block.py, video_utils.py, video_xfields.py, __init__.py)
  • xmodule/assets/video/ (entire directory, 9K+ LOC of JS player assets)
  • xmodule/js/src/video/08_video_auto_advance_control.js
  • lms/templates/video.html, video_modal.html, public_video.html, public_video_share_embed.html
  • xmodule/static/css-builtin-blocks/VideoBlockDisplay.css
  • xmodule/static/css-builtin-blocks/VideoBlockEditor.css
  • Webpack entries VideoBlockDisplay / VideoBlockEditor in webpack.builtinblocks.config.js
• Run smoke tests on the extracted Video block to verify nothing is broken, including transcript upload and public video sharing.

[irfanuddinahmad]

Implementation PR: openedx/openedx-platform#38750