housecleaning: remove nonnullableTypes

lib/src/compiler.dart

 // Copyright (c) 2015, 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.
 
 /// Command line tool to run the checker on a Dart program.
 library dev_compiler.src.compiler;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:math' as math;
 import 'dart:io';
 
 import 'package:analyzer/src/generated/ast.dart' show CompilationUnit;
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show AnalysisEngine, AnalysisContext, ChangeSet, ParseDartTask;
 import 'package:analyzer/src/generated/error.dart'
     show AnalysisError, ErrorSeverity, ErrorType;
 import 'package:analyzer/src/generated/error.dart';
-import 'package:analyzer/src/generated/resolver.dart' show TypeProvider;
 import 'package:analyzer/src/generated/source.dart' show Source;
 import 'package:analyzer/src/task/html.dart';
 import 'package:html/dom.dart' as html;
 import 'package:html/parser.dart' as html;
 import 'package:logging/logging.dart' show Level, Logger, LogRecord;
 import 'package:path/path.dart' as path;
 
-import '../strong_mode.dart' show StrongModeOptions;
-
 import 'analysis_context.dart';
 import 'checker/checker.dart';
 import 'checker/rules.dart';
 import 'codegen/html_codegen.dart' as html_codegen;
 import 'codegen/js_codegen.dart';
 import 'info.dart'
     show AnalyzerMessage, CheckerResults, LibraryInfo, LibraryUnit;
 import 'options.dart';
 import 'report.dart';
 
@@ skipping 476 matching lines @@
     '_rtti.js',
     '_classes.js',
     '_operations.js',
     'dart_runtime.js',
   ];
   files.addAll(corelibOrder.map((l) => l.replaceAll('.', '/') + '.js'));
   return files;
 }();
 
 final _log = new Logger('dev_compiler.src.compiler');