Changed the removed method to the correct one

[leobispo]

'BuildContext' is from 'package:flutter/src/widgets/framework.dart' ('../../../flutter/packages/flutter/lib/src/widgets/framework.dart'). Try correcting the name to the name of an existing method, or defining a method named 'inheritFromWidgetOfExactType'. final w = context.inheritFromWidgetOfExactType(_InjectorInheritedWidget);