debugLastParentDataRefreshIterationCount property
Iteration count of the post-sticky parentData refresh loop on the
last layout. Reset at the top of performLayout. The loop iterates
_children.keys exactly once, so this counter is bounded by
_children.length — verified by
test/sliver_tree/parent_data_refresh_iteration_test.dart (R124).
Diagnostic only; no runtime invariant is enforced by this field.
Implementation
@visibleForTesting
int debugLastParentDataRefreshIterationCount = 0;