core(metrics): handle scheduler.yield#17066
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…ated TBT Fixes massively inflated TBT and Javascript Execution Time metrics when pages use scheduler.yield() or scheduler.postTask() for chunking work. When these trace events are present, the tasks are bounded correctly, so we use their original unthrottled duration to determine if they meet the 50ms long task threshold rather than their simulated (cpu-throttled) duration. Fixes #16183
Adds smoke tests to verify that scheduler.yield and scheduler.postTask tasks are correctly simulated and do not artificially inflate Total Blocking Time during mobile throttling. Fixes #16183
… tasks The original issue reported that both Total Blocking Time (TBT) and JavaScript execution time were being artificially inflated during simulated mobile throttling. While the Total CPU Time math is technically correct across the whole page, the simulated long tasks were appearing in the `long-tasks` audit table. This commit ensures the `long-tasks` audit respects the original unthrottled duration of tasks bounded by `scheduler.yield` or `scheduler.postTask`, preventing them from falsely polluting the list of input delay contributors. Fixes #16183
connorjclark
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Jun 5, 2026
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(draft: AI assisted, I haven't done due diligence yet)
fixes #16183