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  "commit": "9eee9653ddb8bd351d52df89dff395405c1bc9d0",
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  "parents": [
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  "author": {
    "name": "Harry Terkelsen",
    "email": "1961493+harryterkelsen@users.noreply.github.com",
    "time": "Wed Nov 05 14:07:02 2025 -0800"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Wed Nov 05 22:07:02 2025 +0000"
  },
  "message": "[web] Unify Surface code between Skwasm and CanvasKit (#177138)\n\nThis PR introduces a significant refactoring of the web engine\u0027s\nrendering layer by unifying the `Surface` and `Rasterizer`\nimplementations. These components have been moved from being\nrenderer-specific to a generic `compositing` directory, making the\narchitecture more modular and easier to maintain. The rasterizers are\nnow renderer-agnostic and are provided with renderer-specific surface\nfactories via dependency injection. A new `CanvasProvider` abstraction\nhas also been introduced to manage the lifecycle of the underlying\ncanvas elements.\n\nA key outcome of this work is that the Skwasm backend now correctly\nhandles WebGL context loss events. This was achieved by refactoring\n`SkwasmSurface` to allow the Dart side to manage the `OffscreenCanvas`\nlifecycle. A communication channel between the main thread and the web\nworker is now used to gracefully handle context loss and recovery. This\neffort also included fixing several related bugs around surface sizing,\nresource cleanup, and callback handling in multi-surface scenarios.\n\nTo validate these changes, new testing APIs have been added to allow for\nthe creation of renderer-agnostic surface tests. A new test file,\n`surface_context_lost_test.dart`, has been added to verify the context\nloss and recovery behavior across all supported renderers, ensuring the\nnew architecture is robust and reliable.\n\n## Pre-launch Checklist\n\n- [x] I read the [Contributor Guide] and followed the process outlined\nthere for submitting PRs.\n- [x] I read the [Tree Hygiene] wiki page, which explains my\nresponsibilities.\n- [x] I read and followed the [Flutter Style Guide], including [Features\nwe expect every widget to implement].\n- [x] I signed the [CLA].\n- [x] I listed at least one issue that this PR fixes in the description\nabove.\n- [x] I updated/added relevant documentation (doc comments with `///`).\n- [x] I added new tests to check the change I am making, or this PR is\n[test-exempt].\n- [x] I followed the [breaking change policy] and added [Data Driven\nFixes] where supported.\n- [x] All existing and new tests are passing.\n\nIf you need help, consider asking for advice on the #hackers-new channel\non [Discord].\n\n**Note**: The Flutter team is currently trialing the use of [Gemini Code\nAssist for\nGitHub](https://developers.google.com/gemini-code-assist/docs/review-github-code).\nComments from the `gemini-code-assist` bot should not be taken as\nauthoritative feedback from the Flutter team. If you find its comments\nuseful you can update your code accordingly, but if you are unsure or\ndisagree with the feedback, please feel free to wait for a Flutter team\nmember\u0027s review for guidance on which automated comments should be\naddressed.\n\n\u003c!-- Links --\u003e\n[Contributor Guide]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview\n[Tree Hygiene]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md\n[test-exempt]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests\n[Flutter Style Guide]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md\n[Features we expect every widget to implement]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement\n[CLA]: https://cla.developers.google.com/\n[flutter/tests]: https://github.com/flutter/tests\n[breaking change policy]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes\n[Discord]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md\n[Data Driven Fixes]:\nhttps://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md",
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