Use entities in class_stub_generator.

pkg/compiler/lib/src/js_emitter/type_test_registry.dart

Index: pkg/compiler/lib/src/js_emitter/type_test_registry.dart
diff --git a/pkg/compiler/lib/src/js_emitter/type_test_registry.dart b/pkg/compiler/lib/src/js_emitter/type_test_registry.dart
index 24bca0bc71b06d985fce1ecd533cacea88370c78..15f3b5562f3f124f8ba8dd3bc5c853c459b4aac9 100644
--- a/pkg/compiler/lib/src/js_emitter/type_test_registry.dart
+++ b/pkg/compiler/lib/src/js_emitter/type_test_registry.dart
@@ -7,22 +7,15 @@ library dart2js.js_emitter.type_test_registry;
 import '../compiler.dart' show Compiler;
 import '../elements/resolution_types.dart'
     show
-    ResolutionDartType,
-    ResolutionFunctionType,
-    ResolutionInterfaceType,
-    Types,
-    ResolutionTypeVariableType;
+        ResolutionDartType,
+        ResolutionFunctionType,
+        ResolutionInterfaceType,
+        Types,
+        ResolutionTypeVariableType;
 import '../elements/elements.dart'
-    show
-    ClassElement,
-    Element,
-    ElementKind,
-    FunctionElement;
+    show ClassElement, Element, ElementKind, FunctionElement;
 import '../js_backend/js_backend.dart'
-    show
-    JavaScriptBackend,
-    RuntimeTypes,
-    TypeChecks;
+    show JavaScriptBackend, RuntimeTypes, TypeChecks;
 import '../world.dart' show ClosedWorld;
 
 class TypeTestRegistry {