[DevTools] Fix broken commit tree builder for initial operations

[everettbu]

Mirror of facebook/react#35710
Original author: eps1lon

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Summary

Originally thought we can stop sending the root ID entirely but it's used by the commit tree builder. That made me realize react/react#35093 introduced a regression.

Flushing pending events is only safe without a root if we're not profiling or if we're flushing events that don't mutate the tree (e.g. console errors and warnings)

Also removes handling of TREE_OPERATION_REMOVE_ROOT in various frontends since that operation is no longer sent by the backend.

How did you test this change?

• CI

[greptile-apps]

Greptile Overview

Greptile Summary

Fixes regression introduced in PR #35093 where removing the root ID from operations broke the commit tree builder during profiling. The commit tree builder requires the root ID to properly reconstruct the component tree for each commit. This PR adds back the root parameter to flushPendingEvents() and includes the root ID in operations when needed (during profiling or tree mutations), while safely passing null for operations that don't mutate the tree (like error/warning updates). Also cleans up unused TREE_OPERATION_REMOVE_ROOT handling code across frontend components since that operation is no longer sent by the backend.

Confidence Score: 5/5

• This PR is safe to merge with minimal risk
• The fix properly addresses a regression by restoring necessary root ID information for the commit tree builder while maintaining the optimization of passing null when safe. All call sites have been correctly updated with appropriate context-aware parameters (specific root during profiling/tree mutations, null for error/warning updates). The cleanup of unused TREE_OPERATION_REMOVE_ROOT handling is straightforward dead code removal.
• No files require special attention

Important Files Changed

Filename	Overview
packages/react-devtools-shared/src/backend/fiber/renderer.js	Added root parameter to flushPendingEvents() and updated all call sites to pass either a specific root or null based on context (profiling status and operation type)
packages/react-devtools-shared/src/devtools/views/Profiler/CommitTreeBuilder.js	Removed handling code for TREE_OPERATION_REMOVE_ROOT operation that is no longer sent

[greptile-apps]

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[everettbu]

Upstream PR was closed or merged. Code is synced via branch mirror.