Add @overrides to (a lot of) analyzer.

pkg/analyzer/lib/file_system/memory_file_system.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.file_system.memory_file_system;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:core' hide Resource;
 
@@ skipping 11 matching lines @@
 class MemoryResourceProvider implements ResourceProvider {
   final Map<String, _MemoryResource> _pathToResource =
       new HashMap<String, _MemoryResource>();
   final Map<String, String> _pathToContent = new HashMap<String, String>();
   final Map<String, int> _pathToTimestamp = new HashMap<String, int>();
   final Map<String, List<StreamController<WatchEvent>>> _pathToWatchers =
       new HashMap<String, List<StreamController<WatchEvent>>>();
   int nextStamp = 0;
 
   final Context _pathContext;
+  @override
   final AbsolutePathContext absolutePathContext;
 
   MemoryResourceProvider({bool isWindows: false})
       : _pathContext = isWindows ? windows : posix,
         absolutePathContext = new AbsolutePathContext(isWindows);
 
   @override
   Context get pathContext => _pathContext;
 
   /**
@@ skipping 162 matching lines @@
       : super(provider, path);
 
   @override
   Stream<WatchEvent> get changes {
     throw new FileSystemException(path, "File does not exist");
   }
 
   @override
   bool get exists => false;
 
+  @override
   int get modificationStamp {
     int stamp = _provider._pathToTimestamp[path];
     if (stamp == null) {
       throw new FileSystemException(path, "File does not exist");
     }
     return stamp;
   }
 
   String get _content {
     throw new FileSystemException(path, 'File could not be read');
@@ skipping 18 matching lines @@
 /**
  * An in-memory implementation of [File].
  */
 class _MemoryFile extends _MemoryResource implements File {
   _MemoryFile(MemoryResourceProvider provider, String path)
       : super(provider, path);
 
   @override
   bool get exists => _provider._pathToResource[path] is _MemoryFile;
 
+  @override
   int get modificationStamp {
     int stamp = _provider._pathToTimestamp[path];
     if (stamp == null) {
       throw new FileSystemException(path, 'File "$path" does not exist.');
     }
     return stamp;
   }
 
   String get _content {
     String content = _provider._pathToContent[path];
@@ skipping 34 matching lines @@
    * Map from encoded URI/filepath pair to a unique integer identifier.  This
    * identifier is used for equality tests and hash codes.
    *
    * The URI and filepath are joined into a pair by separating them with an '@'
    * character.
    */
   static final Map<String, int> _idTable = new HashMap<String, int>();
 
   final _MemoryFile file;
 
+  @override
   final Uri uri;
 
   /**
    * The unique ID associated with this [_MemoryFileSource].
    */
   final int id;
 
   _MemoryFileSource(_MemoryFile file, Uri uri)
       : uri = uri,
         file = file,
@@ skipping 130 matching lines @@
     }
     return contains(path);
   }
 }
 
 /**
  * An in-memory implementation of [Resource].
  */
 abstract class _MemoryResource implements Resource {
   final MemoryResourceProvider _provider;
+  @override
   final String path;
 
   _MemoryResource(this._provider, this.path);
 
   Stream<WatchEvent> get changes {
     StreamController<WatchEvent> streamController =
         new StreamController<WatchEvent>();
     if (!_provider._pathToWatchers.containsKey(path)) {
       _provider._pathToWatchers[path] = <StreamController<WatchEvent>>[];
     }
@@ skipping 26 matching lines @@
   bool operator ==(other) {
     if (runtimeType != other.runtimeType) {
       return false;
     }
     return path == other.path;
   }
 
   @override
   String toString() => path;
 }