Rename analyzer_experimental to analyzer.

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

 // 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;
 import 'java_core.dart';
 import 'java_engine.dart';
 import 'utilities_collection.dart';
 import 'utilities_general.dart';
 import 'instrumentation.dart';
 import 'error.dart';
 import 'source.dart';
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   }
   void logError2(String message, Exception exception) {
   }
   void logError3(Exception exception) {
   }
   void logInformation(String message) {
   }
   void logInformation2(String message, Exception exception) {
   }
 }