Update InheritedModel doc (#21501)

packages/flutter/lib/src/widgets/inherited_model.dart

@@ -62,14 +62,14 @@ import 'framework.dart';
 ///   final int b;
 ///
 ///   @override
-///   bool updateShouldNotify(ABCModel old) {
-///     return return super.updateShouldNotify(old) || a != old.a || b != old.b;
+///   bool updateShouldNotify(ABModel old) {
+///     return a != old.a || b != old.b;
 ///   }
 ///
 ///   @override
-///   bool updateShouldNotifyDependent(ABCModel old, Set<String> dependencies) {
-///     return (a != old.a && dependencies.contains('a'))
-///         || (b != old.b && dependencies.contains('b'))
+///   bool updateShouldNotifyDependent(ABModel old, Set<String> aspects) {
+///     return (a != old.a && aspects.contains('a'))
+///         || (b != old.b && aspects.contains('b'))
 ///   }
 ///
 ///   // ...