Merge CommonElements and BackendHelpers!

tests/compiler/dart2js/minimal_resolution_test.dart

Index: tests/compiler/dart2js/minimal_resolution_test.dart
diff --git a/tests/compiler/dart2js/minimal_resolution_test.dart b/tests/compiler/dart2js/minimal_resolution_test.dart
index a267acc81dea03f745c0b242c8c7357a81bc1289..68c080d7bd0c492fa65626993ee4f5fe2cf1228c 100644
--- a/tests/compiler/dart2js/minimal_resolution_test.dart
+++ b/tests/compiler/dart2js/minimal_resolution_test.dart
@@ -5,10 +5,11 @@
 // Test that elements are not needlessly required by dart2js.
 
 import 'package:async_helper/async_helper.dart';
+import 'package:compiler/src/common/names.dart';
 import 'package:compiler/src/compiler.dart';
 import 'package:compiler/src/elements/elements.dart';
 import 'package:compiler/src/enqueue.dart';
-import 'package:compiler/src/js_backend/backend_helpers.dart';
+import 'package:compiler/src/js_backend/backend.dart' show JavaScriptBackend;
 import 'package:expect/expect.dart';
 import 'memory_compiler.dart';
 
@@ -50,7 +51,7 @@ analyze(String code,
   checkInstantiated(compiler, coreLibrary.find('Deprecated'), deprecatedClass);
 
   LibraryElement jsHelperLibrary =
-      compiler.libraryLoader.lookupLibrary(BackendHelpers.DART_JS_HELPER);
+      compiler.libraryLoader.lookupLibrary(Uris.dart__js_helper);
   jsHelperLibrary.forEachLocalMember((Element element) {
     Uri uri = element.compilationUnit.script.resourceUri;
     if (element.isClass && uri.path.endsWith('annotations.dart')) {