Minor clarifications in docs (#11171)

packages/flutter/lib/src/services/image_provider.dart

@@ -388,7 +388,7 @@ abstract class AssetBundleImageProvider extends ImageProvider<AssetBundleImageKe
 
 /// Fetches the given URL from the network, associating it with the given scale.
 ///
-/// Cache headers from the server are ignored.
+/// The image will be cached regardless of cache headers from the server.
 // TODO(ianh): Find some way to honour cache headers to the extent that when the
 // last reference to an image is released, we proactively evict the image from
 // our cache if the headers describe the image as having expired at that point.

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

@@ -94,7 +94,9 @@ class NotificationListener<T extends Notification> extends StatelessWidget {
     this.onNotification,
   }) : super(key: key);
 
-  /// The widget below this widget in the tree.
+  /// The widget directly below this widget in the tree.
+  ///
+  /// This is not necessarily the widget that dispatched the notification.
   final Widget child;
 
   /// Called when a notification of the appropriate type arrives at this