fix #43, remove => workaround

lib/src/options.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.
 
 /// Set of flags and options passed to the compiler
 
 import 'dart:io';
 
 import 'package:args/args.dart';
 import 'package:cli_util/cli_util.dart' show getSdkDir;
@@ skipping 59 matching lines @@
 
   /// Output directory for generated code.
   final String outputDir;
 
   /// Emit Closure Compiler-friendly code.
   final bool closure;
 
   /// Enable ES6 destructuring of named parameters.
   final bool destructureNamedParams;
 
-  /// Whether to emit a workaround for missing arrow function bind-this in
-  /// other V8 builds
-  final bool arrowFnBindThisWorkaround;
-
   /// Which module format to support.
   /// Currently 'es6' and 'legacy' are supported.
   final ModuleFormat moduleFormat;
 
   const CodegenOptions(
       {this.emitSourceMaps: true,
       this.forceCompile: false,
       this.closure: _CLOSURE_DEFAULT,
       this.destructureNamedParams: _DESTRUCTURE_NAMED_PARAMS_DEFAULT,
       this.outputDir,
-      this.arrowFnBindThisWorkaround: false,
       this.moduleFormat: ModuleFormat.legacy});
 }
 
 /// Options for devrun.
 class RunnerOptions {
   /// V8-based binary to be used to run the .js output (d8, iojs, node).
   /// Can be just the executable name if it's in the path, or a path to the
   /// executable.
   final String v8Binary;
 
@@ skipping 128 matching lines @@
     customUrlMappings[splitMapping[0]] = splitMapping[1];
   }
 
   return new CompilerOptions(
       codegenOptions: new CodegenOptions(
           emitSourceMaps: args['source-maps'],
           forceCompile: args['force-compile'] || serverMode,
           closure: args['closure'],
           destructureNamedParams: args['destructure-named-params'],
           outputDir: outputDir,
-          arrowFnBindThisWorkaround: args['arrow-fn-bind-this'],
           moduleFormat: parseModuleFormat(args['modules'])),
       sourceOptions: new SourceResolverOptions(
           useMockSdk: args['mock-sdk'],
           dartSdkPath: sdkPath,
           useImplicitHtml: serverMode &&
               args.rest.length == 1 &&
               args.rest[0].endsWith('.dart'),
           customUrlMappings: customUrlMappings,
           useMultiPackage: args['use-multi-package'],
           packageRoot: args['package-root'],
@@ skipping 43 matching lines @@
   ..addOption('package-paths',
       help: 'if using the multi-package resolver, the list of directories to\n'
           'look for packages in.',
       defaultsTo: '')
   ..addOption('resources',
       help: 'Additional resources to serve', defaultsTo: '')
   ..addFlag('source-maps',
       help: 'Whether to emit source map files', defaultsTo: true)
   ..addOption('runtime-dir',
       help: 'Where to find dev_compiler\'s runtime files', defaultsTo: null)
-  ..addFlag('arrow-fn-bind-this',
-      help: 'Work around `this` binding in => functions')
   ..addOption('modules',
       help: 'Which module pattern to emit',
       allowed: ModuleFormat.values.map(getEnumName).toList(),
       allowedHelp: {
         getEnumName(ModuleFormat.es6): 'es6 modules',
         getEnumName(ModuleFormat.legacy):
             'a custom format used by dartdevc, similar to AMD',
         getEnumName(ModuleFormat.node):
             'node.js modules (https://nodejs.org/api/modules.html)'
       },
@@ skipping 89 matching lines @@
     // The pub-cache directory is two levels up, but we verify that the layout
     // looks correct.
     if (path.basename(dir) != 'dev_compiler') return null;
     dir = path.dirname(dir);
     if (path.basename(dir) != 'global_packages') return null;
     dir = path.dirname(dir);
     return path.join(dir, cacheDir, 'lib', 'runtime');
   }
   return null;
 }