Correctly compile unresolved for-in loops.

dart/tests/compiler/dart2js/deferred_load_graph_segmentation_test.dart

 // Copyright (c) 2013, 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.
 
 // Test of the graph segmentation algorithm used by deferred loading
 // to determine which elements can be deferred and which libraries
 // much be included in the initial download (loaded eagerly).
 
 import 'package:expect/expect.dart';
-import 'dart:async' show Future;
-import 'dart:uri' show Uri;
-import 'dart:io';
-
-import '../../../sdk/lib/_internal/compiler/implementation/apiimpl.dart'
-       show Compiler;
+import 'memory_source_file_helper.dart';
 
 import '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart'
        as dart2js;
 
-import '../../../sdk/lib/_internal/compiler/implementation/filenames.dart'
-       show getCurrentDirectory, nativeToUriPath;
-
-import '../../../sdk/lib/_internal/compiler/implementation/source_file.dart'
-       show SourceFile;
-
-import '../../../sdk/lib/_internal/compiler/implementation/source_file_provider.dart'
-       show FormattingDiagnosticHandler,
-            SourceFileProvider;
-
-class MemorySourceFileProvider extends SourceFileProvider {
-  Future<String> readStringFromUri(Uri resourceUri) {
-    if (resourceUri.scheme != 'memory') {
-      return super.readStringFromUri(resourceUri);
-    }
-    String source = MEMORY_SOURCE_FILES[resourceUri.path];
-    // TODO(ahe): Return new Future.immediateError(...) ?
-    if (source == null) throw 'No such file $resourceUri';
-    String resourceName = '$resourceUri';
-    this.sourceFiles[resourceName] = new SourceFile(resourceName, source);
-    return new Future.immediate(source);
-  }
-}
-
 void main() {
   Uri cwd = getCurrentDirectory();
   Uri script = cwd.resolve(nativeToUriPath(new Options().script));
   Uri libraryRoot = script.resolve('../../../sdk/');
   Uri packageRoot = script.resolve('./packages/');
 
+  MemorySourceFileProvider.MEMORY_SOURCE_FILES = MEMORY_SOURCE_FILES;
   var provider = new MemorySourceFileProvider();
   var handler = new FormattingDiagnosticHandler(provider);
 
   Compiler compiler = new Compiler(provider.readStringFromUri,
                                    (name, extension) => null,
                                    handler.diagnosticHandler,
                                    libraryRoot,
                                    packageRoot,
                                    ['--analyze-only']);
   compiler.run(new Uri('memory:main.dart'));
@@ skipping 38 matching lines @@
 class MyClass {
   const MyClass();
 
   foo(x) {
     new Expando();
     return (x - 3) ~/ 2;
   }
 }
 """,
 };