remove unused imports

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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.source.io;
 
 import 'dart:collection';
 
 import 'engine.dart';
 import 'java_core.dart';
 import 'java_engine.dart';
 import 'java_io.dart';
 import 'source.dart';
-import 'utilities_general.dart';
 
 export 'source.dart';
 
 /**
  * Instances of the class [DirectoryBasedSourceContainer] represent a source container that
  * contains all sources within a given directory.
  */
 class DirectoryBasedSourceContainer implements SourceContainer {
   /**
    * The container's path (not `null`).
@@ skipping 510 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;
 }