Implement fromEnvironment on bool, int, String in dart2js.

sdk/lib/_internal/compiler/implementation/apiimpl.dart

 // Copyright (c) 2012, 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.
 
 library leg_apiimpl;
 
 import 'dart:async';
 
 import '../compiler.dart' as api;
 import 'dart2jslib.dart' as leg;
 import 'tree/tree.dart' as tree;
 import 'elements/elements.dart' as elements;
 import 'ssa/tracer.dart' as ssa;
 import '../../libraries.dart';
 import 'source_file.dart';
 
 class Compiler extends leg.Compiler {
   api.CompilerInputProvider provider;
   api.DiagnosticHandler handler;
   final Uri libraryRoot;
   final Uri packageRoot;
   List<String> options;
+  Map<String, dynamic> environment;
   bool mockableLibraryUsed = false;
   final Set<String> allowedLibraryCategories;
 
   Compiler(this.provider,
            api.CompilerOutputProvider outputProvider,
            this.handler,
            this.libraryRoot,
            this.packageRoot,
-           List<String> options)
+           List<String> options,
+           this.environment)
       : this.options = options,
         this.allowedLibraryCategories = getAllowedLibraryCategories(options),
         super(
             tracer: new ssa.HTracer(
                 ssa.GENERATE_SSA_TRACE ? outputProvider('dart', 'cfg') : null),
             outputProvider: outputProvider,
             enableTypeAssertions: hasOption(options, '--enable-checked-mode'),
             enableUserAssertions: hasOption(options, '--enable-checked-mode'),
             trustTypeAnnotations:
                 hasOption(options, '--trust-type-annotations'),
@@ skipping 280 matching lines @@
       diagnoseCrashInUserCode('Uncaught exception in input provider', ex, s);
       rethrow;
     }
   }
 
   void diagnoseCrashInUserCode(String message, exception, stackTrace) {
     hasCrashed = true;
     print('$message: ${tryToString(exception)}');
     print(tryToString(stackTrace));
   }
+
+  fromEnvironment(String name) => environment[name];
 }