Fix for getFilesForPath() for a generated file.

pkg/analyzer/lib/src/dart/analysis/file_state.dart

 // Copyright (c) 2016, 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.
 
 import 'dart:convert';
 import 'dart:typed_data';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/error/listener.dart';
@@ skipping 574 matching lines @@
    */
   FileState getFileForPath(String path) {
     FileState file = _pathToCanonicalFile[path];
     if (file == null) {
       File resource = _resourceProvider.getFile(path);
       Source fileSource = resource.createSource();
       Uri uri = _sourceFactory.restoreUri(fileSource);
       // Try to get the existing instance.
       file = _uriToFile[uri];
       // If we have a file, call it the canonical one and return it.
-      if (file != null) {
+      if (file != null && file.path == path) {
         _pathToCanonicalFile[path] = file;
         return file;
       }
       // Create a new file.
       FileSource uriSource = new FileSource(resource, uri);
       file = new FileState._(this, path, uri, uriSource);
       _uriToFile[uri] = file;
       _addFileWithPath(path, file);
       _pathToCanonicalFile[path] = file;
       file.refresh();
@@ skipping 74 matching lines @@
         .where((f) => f._transitiveFiles == null)
         .toSet();
   }
 
   Set<FileState> get filesWithoutTransitiveSignature {
     return state._uriToFile.values
         .where((f) => f._transitiveSignature == null)
         .toSet();
   }
 }