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

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

Index: pkg/analyzer/lib/src/generated/sdk.dart
diff --git a/pkg/analyzer/lib/src/generated/sdk.dart b/pkg/analyzer/lib/src/generated/sdk.dart
index b16e31d55f3c9a0200457f755780d0686b5a4356..d133f1d2d1a69b2997653179edefa8740c2158bc 100644
--- a/pkg/analyzer/lib/src/generated/sdk.dart
+++ b/pkg/analyzer/lib/src/generated/sdk.dart
@@ -243,7 +243,7 @@ class SdkLibrariesReader_LibraryBuilder extends RecursiveAstVisitor<Object> {
   /**
    * A flag indicating whether the dart2js path should be used when it is available.
    */
-  bool _useDart2jsPaths = false;
+  final bool _useDart2jsPaths;
 
   /**
    * The library map that is populated by visiting the AST structure parsed from the contents of
@@ -257,9 +257,7 @@ class SdkLibrariesReader_LibraryBuilder extends RecursiveAstVisitor<Object> {
    *
    * @param useDart2jsPaths `true` if the dart2js path should be used when it is available
    */
-  SdkLibrariesReader_LibraryBuilder(bool useDart2jsPaths) {
-    this._useDart2jsPaths = useDart2jsPaths;
-  }
+  SdkLibrariesReader_LibraryBuilder(this._useDart2jsPaths);
 
   /**
    * Return the library map that was populated by visiting the AST structure parsed from the