[ResizeObserver 1/3] Add new hook shadowTreeDidCommit - #57721
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paradowstack wants to merge 2 commits into
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[ResizeObserver 1/3] Add new hook shadowTreeDidCommit#57721paradowstack wants to merge 2 commits into
paradowstack wants to merge 2 commits into
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Summary:
ShadowTreealready computes the set of nodes whose layout changed on every commit (affectedLayoutableNodes), but today it's only consumed internally byShadowTree::emitLayoutEvents.This adds a
shadowTreeDidCommit(shadowTree, rootShadowNode, affectedLayoutableNodes)method toShadowTreeDelegateandUIManagerCommitHookso other systems can react to layout changes after a commit.ShadowTreecalls it once the new revision is installed, andUIManagerforwards it to the registered commit hooks.Both declarations have no-op defaults, so nothing observes the hook yet — this is inert on its own. It's the shared signal the next two PRs build on (extracting
onLayoutemission, andResizeObserver), so neither has to re-derive which nodes changed layout.Changelog:
[INTERNAL] [ADDED] - Add
shadowTreeDidCommitcommit hook exposing the nodes with layout changes after each commitTest Plan:
No behavior change: the hook has no-op defaults and no consumer in this PR. Existing Fabric commit/mounting tests pass.