Support iife heuristic in DDC

pkg/dev_compiler/lib/src/compiler/module_builder.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.
 
 import 'package:args/args.dart' show ArgParser, ArgResults;
 import 'package:path/path.dart' as path;
 
 import '../js_ast/js_ast.dart';
 import 'js_names.dart';
 
@@ skipping 178 matching lines @@
               .add(js.statement('#.# = #;', [exportsVar, name.name, name]));
         }
       }
     }
 
     var resultModule =
         js.call("function(#) { 'use strict'; #; }", [parameters, statements]);
     var functionName =
         'load__' + pathToJSIdentifier(module.name.replaceAll('.', '_'));
     resultModule =
-        new NamedFunction(new Identifier(functionName), resultModule);
+        new NamedFunction(new Identifier(functionName), resultModule, true);
 
     var moduleDef = js.statement("dart_library.library(#, #, #, #)", [
       js.string(module.name, "'"),
       new LiteralNull(),
       js.commentExpression(
           "Imports", new ArrayInitializer(importNames, multiline: true)),
       resultModule
     ]);
     return new Program(<ModuleItem>[moduleDef]);
   }
@@ skipping 85 matching lines @@
         assert(names != null);
         for (var name in names) {
           exportedProps.add(new Property(js.string(name.name), name));
         }
       }
       statements.add(js.comment('Exports:'));
       statements.add(
           new Return(new ObjectInitializer(exportedProps, multiline: true)));
     }
 
+    // TODO(vsm): Consider using an immediately invoked named function pattern
+    // (see legacy code above).
     var block = singleOutFile
         ? js.statement("define(#, #, function(#) { 'use strict'; #; });", [
             js.string(module.name, "'"),
             new ArrayInitializer(dependencies),
             fnParams,
             statements
           ])
         : js.statement("define(#, function(#) { 'use strict'; #; });",
             [new ArrayInitializer(dependencies), fnParams, statements]);
 
@@ skipping 27 matching lines @@
   // Ensure the identifier first character is not numeric and that the whole
   // identifier is not a keyword.
   if (result.startsWith(new RegExp('[0-9]')) || invalidVariableName(result)) {
     return '\$$result';
   }
   return result;
 }
 
 // Invalid characters for identifiers, which would need to be escaped.
 final _invalidCharInIdentifier = new RegExp(r'[^A-Za-z_$0-9]');