Fix for translation of \!= to \!identical(), but use == and \!= for Enum.

pkg/analyzer/lib/src/generated/sdk_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.sdk.io;
 
 import 'java_core.dart';
@@ skipping 415 matching lines @@
  *     "compiler/compiler.dart",
  *     category: "Tools",
  *     platforms: 0),
  * };
  * </pre>
  */
 class SdkLibrariesReader {
   /**
    * A flag indicating whether the dart2js path should be used when it is available.
    */
-  bool _useDart2jsPaths = false;
+  final bool _useDart2jsPaths;
 
   /**
    * Initialize a newly created library reader to use the dart2js path if the given value is
    * `true`.
    *
    * @param useDart2jsPaths `true` if the dart2js path should be used when it is available
    */
-  SdkLibrariesReader(bool useDart2jsPaths) {
-    this._useDart2jsPaths = useDart2jsPaths;
-  }
+  SdkLibrariesReader(this._useDart2jsPaths);
 
   /**
    * Return the library map read from the given source.
    *
    * @param file the [File] of the library file
    * @param libraryFileContents the contents from the library file
    * @return the library map read from the given source
    */
   LibraryMap readFromFile(JavaFile file, String libraryFileContents) => readFromSource(new FileBasedSource.con2(file, UriKind.FILE_URI), libraryFileContents);
 
@@ skipping 10 matching lines @@
     Parser parser = new Parser(source, errorListener);
     CompilationUnit unit = parser.parseCompilationUnit(scanner.tokenize());
     SdkLibrariesReader_LibraryBuilder libraryBuilder = new SdkLibrariesReader_LibraryBuilder(_useDart2jsPaths);
     // If any syntactic errors were found then don't try to visit the AST structure.
     if (!errorListener.errorReported) {
       unit.accept(libraryBuilder);
     }
     return libraryBuilder.librariesMap;
   }
 }