Registration-based approach to cross frame support.

pkg/dev_compiler/lib/src/compiler/code_generator.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 'dart:collection' show HashMap, HashSet;
 import 'dart:math' show min, max;
 
 import 'package:analyzer/analyzer.dart' hide ConstantEvaluator;
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 1768 matching lines @@
           .where((peer) => !peer.startsWith("!"))
           .toList();
     } else {
       return [];
     }
   }
 
   void _registerExtensionType(
       ClassElement classElem, String jsPeerName, List<JS.Statement> body) {
     if (jsPeerName != null) {
-      body.add(_callHelperStatement('registerExtension(#.global.#, #);', [
-        _runtimeModule,
-        _propertyName(jsPeerName),
-        _emitTopLevelName(classElem)
-      ]));
+      body.add(_callHelperStatement('registerExtension(#, #);',

[Jennifer Messerly, 2017/07/14 19:38:08]

oh wow, this is much cleaner :)

+          [js.string(jsPeerName), _emitTopLevelName(classElem)]));
     }
   }
 
   JS.Statement _setBaseClass(ClassElement classElem, JS.Expression className,
       List<String> jsPeerNames, List<JS.Statement> body) {
     var typeFormals = classElem.typeParameters;
     if (jsPeerNames.length == 1 && typeFormals.isNotEmpty) {
       var newBaseClass = _callHelper('global.#', jsPeerNames[0]);
       body.add(_callHelperStatement(
           'setExtensionBaseClass(#, #);', [className, newBaseClass]));
@@ skipping 4160 matching lines @@
   if (targetIdentifier.staticElement is! PrefixElement) return false;
   var prefix = targetIdentifier.staticElement as PrefixElement;
 
   // The library the prefix is referring to must come from a deferred import.
   var containingLibrary = resolutionMap
       .elementDeclaredByCompilationUnit(target.root as CompilationUnit)
       .library;
   var imports = containingLibrary.getImportsWithPrefix(prefix);
   return imports.length == 1 && imports[0].isDeferred;
 }