[DevTools] Fix commit index reset when switching profiler roots

[everettbu]

Mirror of facebook/react#35672
Original author: hoxyq

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Fixes react/react#31463, react/react#30114.

When switching between roots in the profiler flamegraph, the commit index was preserved from the previous root. This caused an error "Invalid commit X. There are only Y commits." when the new root had fewer commits than the selected index.

This fix resets the commit index to 0 (or null if no commits) when the commitData changes, which happens when switching roots.

[greptile-apps]

Greptile Overview

Greptile Summary

Fixed a bug where switching between profiler roots with different commit counts caused an "Invalid commit X" error. The fix adds a check in useCommitFilteringAndNavigation that resets the commit index to 0 (or null if no commits) whenever the commitData changes, which happens when switching roots.

• Implemented commit index reset logic using the React state pattern to detect commitData changes
• Added a comprehensive test case that verifies the behavior with two roots having different commit counts (5 vs 2)
• The test confirms that navigating to commit index 3 in the first root, then switching to the second root (which only has 2 commits) properly resets to index 0

Confidence Score: 5/5

• This PR is safe to merge with minimal risk
• The fix is well-targeted and uses an established React pattern for detecting prop changes. The comprehensive test case covers the exact bug scenario with multiple roots and different commit counts
• No files require special attention

Important Files Changed

Filename	Overview
packages/react-devtools-shared/src/devtools/views/Profiler/useCommitFilteringAndNavigation.js	Added commit index reset logic when commitData changes to prevent invalid index errors when switching between roots
packages/react-devtools-shared/src/tests/profilerContext-test.js	Added comprehensive test case to verify commit index resets correctly when switching between profiler roots with different commit counts

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[everettbu]

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