debugAssertChildListLocked method Null safety
In debug mode, asserts that this manager is not expecting any modifications to the RenderSliverMultiBoxAdaptor's child list.
This function always returns true.
The manager is not required to track whether it is expecting modifications to the RenderSliverMultiBoxAdaptor's child list and can simply return true without making any assertions.
Implementation
bool debugAssertChildListLocked() => true;