FileSystemModifyEvent.contentChanged issue

[sgrekhov]

Please see https://api.dartlang.org/stable/1.24.2/dart-io/FileSystemModifyEvent/contentChanged.html

bool contentChanged
final
If the content was changed and not only the attributes, contentChanged is true.

It is not quite clean what is "content change". For example setting file lastAcessed generates FileSystemModifyEvent with the contentChanged set to true. Is this expected? Please change FileSystemModifyEvent.contentChanged documentation to clearly say in what cases this property should be true