byIcon method
Finds Icon widgets containing icon data equal to the icon
argument.
Sample code
expect(find.byIcon(Icons.inbox), findsOneWidget);
If the skipOffstage
argument is true (the default), then this skips
nodes that are Offstage or that are from inactive Routes.
Implementation
Finder byIcon(IconData icon, { bool skipOffstage = true }) => _IconWidgetFinder(icon, skipOffstage: skipOffstage);