debugProfileBuildsEnabled top-level property
read / write
Adds Timeline events for every Widget built.
For details on how to use Timeline events in the Dart Observatory to optimize your app, see https://fuchsia.googlesource.com/sysui/+/master/docs/performance.md
See also debugProfilePaintsEnabled, which does something similar but for painting, and debugPrintRebuildDirtyWidgets, which does something similar but reporting the builds to the console.
Implementation
bool debugProfileBuildsEnabled = false