Remove final references to PackageUriResolver

pkg/analyzer/lib/src/generated/source_io.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.generated.source_io;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_core.dart';
@@ skipping 332 matching lines @@
 }
 
 /**
  * Instances of the class `PackageUriResolver` resolve `package` URI's in the context of
  * an application.
  *
  * For the purposes of sharing analysis, the path to each package under the "packages" directory
  * should be canonicalized, but to preserve relative links within a package, the remainder of the
  * path from the package directory to the leaf should not.
  */
+@deprecated
 class PackageUriResolver extends UriResolver {
   /**
    * The name of the `package` scheme.
    */
   static String PACKAGE_SCHEME = "package";
 
   /**
    * Log exceptions thrown with the message "Required key not available" only once.
    */
   static bool _CanLogRequiredKeyIoException = true;
@@ skipping 204 matching lines @@
   }
 
   /**
    * Return `true` if the given URI is a `file` URI.
    *
    * @param uri the URI being tested
    * @return `true` if the given URI is a `file` URI
    */
   static bool isFileUri(Uri uri) => uri.scheme == FILE_SCHEME;
 }