b/238879865

MinimumTapTargetGuideline has logic to detect and skip elements that are scrolled partially off screen. However, this logic is flawed. It only checks for widgets that are at the edge of the physical screen, which omits the common case where the Scrollable container itself doesn't touch the edge of the screen.

Consider a screen with an AppBar and a long scrollable widget beneath it. Something like

Scaffold(
  appBar: AppBar(title: Text('Foo')),
  body: ListView(children: buildChildren()),
)

If a widget is partially visible at the top of the ListView, it will still be beneath the AppBar, not at the edge of the device screen, therefore it may fail the MinimumTapTargetGuideline erroneously.